Will the GCB Forgive All Sins?

Thoughts; you have a lot of work to do in explaining how God can forgive a person who doesn't want to be forgiven. I see it like a square circle; it's simply a logical impossibility. The person doesn't want to be in the presence of God, and so God doesn't force Himself upon them. It defeats the point for God to forgive them and bring them into His presence, because the presence of God, to them, is more Hell than Hell is.

One common interpretation among Catholics is that the blasphemy against the Holy Spirit in question is final impenitence. More background information can be found here:
http://www.newadvent.org/cathen/07409a.htm
http://www.newadvent.org/summa/3014.htm

I think a more traditionally orthodox formulation of 1) would be:

Necessarily, the Greatest Conceivable Being (GCB) will forgive all sins of which the sinner is repentent.

When I was at school, I was taught that the only person capable of an eternal sin is the devil. As I understood it, the point was that an eternal sin requires an awareness of eternity. Luke 12v10 fits this well - it could be translated as "He who blasphemes against the Holy Spirit will not be forgiven." However, Mark's version does make it sound as though this is the kind of sin anyone might commit, indeed, in context, the most obvious explanation is that those who just said Jesus cast out demons by the power of Beelzebub were guilty of just this sin.

Why is it necessary that the GCB forgive all sins? It seems that your starting point is an assumption that you offer no support for.

Andrew,
I think what your case requires is a further analysis of the concept of forgiveness and what it entails. (My favorite books on the topic, personally, are Chris Brauns' Unpacking Forgiveness and Richard Swinburne's Responsibility and Atonement.) You appear, from the comments, to be espousing a concept of forgiveness that isn't universally shared by any means. It seems that you construe forgiveness as a mental state in which grievances for past acts are potentially released; I would describe this as merely preparation for forgiveness, not forgiveness itself. Following Brauns and (IIRC) Swinburne, I would maintain, like Kevin, that forgiveness of the unrepentant is not possible, or at the very least not obviously a greater good than non-forgiveness for the sake of justice. (Regarding your last comment, depending on what notion of forgiveness we use, I would disagree with your intuition that the mother forgiving an unrepentant son is better than the other mother; I would actually contend the converse.)

Even if one maintains that 'forgiveness without repentance' is viable and plausible, premise (2) relies on the assumption that this is the notion of forgiveness employed by Jesus in Luke 12:10; if it is not, then premise (2) may be as questionable as premise (1) would be under the 'forgiveness requires repentance' interpretation of forgiveness.

For that reason, I don't think the argument holds water. Under one notion of forgiveness, I think (1) false; under the other, I think (2) false. In neither case do I see good reason to believe both (1) and (2), and thus no good reason to accept (3).

...you could deny (1) by saying that it is not better to forgive a nonrepentent sinner than to not forgive the nonrepentent sinner. Hence, it is no problem for the GCB to not forgiven unrepentent sinners. But compare a mother who has forgiven her unrepentent son and the mother who has not. The former mother seems to have a good quality that the other mother lacks. At least it seems to me that way.

Andrew,

A way to defend your intuition, which seems right to me as well. It's a bit rough, but something like this.

(1) If S does not forgive R for P, then R remains indebted to S for P.

(2) If S does forgive R for P, then R is no longer in debt to S for P.

(3) The greater the wrong in P, the greater the debt S releases in forgiving R.

(4) If R does P and does not repent then R is in greater debt to S than he would be had he done P and repented.

(5) If S forgives R for doing-P-and-not-repenting, then S relieves a greater debt.

(6) If S relieves a greater debt, then S forgives more.

(7) If S forgives more, then S is more forgiving.

(8) If S is more forgiving, then S is morally better.

(9) If S forgives R for doing-P-and-not-repenting, then S is morally better.

I wonder if the distinction between objective and subjective justification is relevant here. The good news of the Gospel is precisely the fact that "your sins are forgiven;" that is, in the death and resurrection of Jesus, all sins are (objectively) forgiven, but only those who believe this good news (subjectively) receive forgiveness. So God does forgive all sins, satisfying (1), and (2) is an incorrect interpretation of what Jesus said; He meant that whoever blasphemes against the Holy Spirit will never experience God's forgiveness.

Andrew, I guess it could be wrong, but (8) seems close to apriori true to me.

It seems to me that we ought to be agnostic to premise 1 because it seems that there could be greater goods that could be accomplished by the greatest possible being not forgiving sins, namely: showing his justice and his hatred toward sin for all eternity. However, it also seems that one could say that he would also be equally good that he forgives people for all eternity because it is good to be merciful and gracious towards persons. Either way: premise 1 seems unjustified.

Andrew; I suppose I was reading you differently you meant. In that case, I don't see what your argument accomplishes. Could you explain what you mean by "forgiveness," and what God forgiving someone accomplishes?

Hello Andrew:

Well some might question the use of forgiveness and punishment (I would for one). After all if one is forgiven then the wrong is let go of without just punishment. If one is punished for the crime then there is no forgiveness but only justice (nothing needs to be forgiven if payment is made). But with that being said, it seems that you might being using different terms than I am, so I will addressed what you have said presupposing the terms as you have seem to use them.

It seems that we can conceive of instances were a child commits an act so terrible like buying a guy and murdered all the parents family and friends out of unreasonable hate for their parents. No punishment would really do and it would be just for parents to never forgive their child for such an act (they cannot replace all the people the child has brutally murder). I would also question the comparison to the position that we are in with God and that we are with parents. Parents are not the greatest good, but God seems to be. If we sin against the greatest good which has the property of maximal justice it seems we might expect the punishment for wrong doing to be qualitatively different. Perhaps it is contrary to God's nature as the greatest possible being to forgive all sins because of his maximal justice and the fact that it would be good according to his justice to actualize instances were he gets to display eternal hatred against sin.

Again, it seems to me that one can construct a case that opposite to yours that seems to carry the same warrant. Hence, I would think that one ought to be agnostic with respect to premise 1. But I must say your argument is very interesting to me. Keep up the good work.

Andrew,

I want to challenge your response to Nathanael Taylor. You take it that S can forgive S* for A-ing even though S justly punishes S for S* for A-ing. Example? Children being punished by parents and yet parents forgive them.

Problem: people punish their children for a variety of reasons, not all are retributive. Parents may see children as not fully developed agents. Punishment occurs not because the child deserves in the full sense whatever they get. Punishment is a means to their proper moral development (at least that is the thought behind so punishing them). So use an example where S is not doing some act to S* (that is, punishing S*) for reasons of moral utility.

Example: Jones hits John because John told Jones that the guy with 10 coins in his pocket will get the job. John is much bigger than Jones and is not threatened by Jones's wimpy hits. John says: "I forgive you. But now it occurs to me that you shouldn't hit me, and such acts are punishable. It turns out that you now do not get the job."

Is your intuition here that John is correct when he says he forgives Jones?

Andrew, the conclusion of your original argument was "God, as conceived of by Jesus, is not the GCB." I find that most of the entries so far are persuading me that this conclusion is correct. For a Christian who is committed to Perfect Being theology, this will be a problem, but other Christians might think this just shows a flaw in the whole GCB approach.

Here's why I say this. The best candidate for a sin that the GCB cannot forgive continued non-repentance, so cnr seems to be the best candidate advanced so far, within the framework Theology, for being an unforgiveable sin. If such sins cannot be forgiven, that seems to be a necessary truth. But now, I try to fit this into the context of Jesus' remarks.

"You cast out demons by the power of Beelzebub."
"Nonsense: demons don't fight against other demons. By the way, continued non-repentance is unforgiveable - interesting fact, eh?"

Sorry if this seems like an unfair caricature of what anyone here is saying. I'm sure that nobody is seriously proposing that we can make sense of the verse by substituting a philosophical paraphrase. But the task of reconciling Jesus' conception of God with the GCB will only be complete when you have a plausible interpretation of Jesus' words in context, and I don't sense that the debate is heading in that direction.

Hello Andrew,

My intuitions would lead me to think that when S punishes S* for a evil action A then S has not forgiven S* but rather S* has paid his due and there is no more debt for just retribution (by my definition of just punishment). But in the case when S forgives S* for an evil action A that forgiveness by definition entails that there is no retributive punishment for an evil action A performed by S*. I should say that you are right in thinking that I would agree with that.

Hello Ben,

I am a Christian and I hold to Perfect being theology. It would seem that Jesus' comments are not all that out of place since in the proceeding context of Matthew 12:32 (the place where Jesus mentions the unforgivable sin) he goes on to condemn the Pharisees in verses 33-40. Furthermore, the reason for Jesus' entire discourse was to respond to the Pharisees who were rejecting Jesus miracles in verses 24-25. I think when one combines this with systematic considerations and looks at the book of Hebrews chapters 6 and 10 they will find in these chapters non- repentant is the grounds by which individuals are not saved. So it seems clear that not repenting for ones sins is the unforgivable sin. Hence, I do not think you have defeated the unrepentant interpretation of Matthew 12. But the Matthew text is disputed among theologians of many different strips.

Wolterstorff thinks that a conceptually necessary condition for x to forgive y is that y accept x's offer of forgiveness. Assuming further than an acceptance of an offer of forgiveness has to be free, it is impossible for a GCB, or anybody else, to forgive a sin that the person does not in fact agree to have forgiven. Therefore, (1) is false.

And maybe the sin against the Holy Spirit is a definitive unwillingness to be forgiven.

Now, I think Wolterstorff is wrong about forgiveness. One can forgive even though one's forgiveness is rejected.

But four further moves can be made.

The somewhat easier is the Molinist move. Suppose the GCB knows who would and who would not freely accept his forgiveness. Then he might very reasonably not extend forgiveness to those who would not in fact accept the forgiveness. There seems to be no failure in goodness there. So if Molinism is true, (1) is false.

The somewhat harder is that it seems reasonable for the GCB to refuse to forgive the sins of those who have in a definitive way--in whatever way is established for definitive declarations of this sort (say, by final impenitence)--rejected his forgiveness.

The last move is to reconcile Wolterstorff with common sense and say that "forgiveness" sometimes is used as entailing a free reconciliation and sometimes as entailing just a unilateral offer, and then one says that in Mark 3:28-29, "forgiveness" is used as entailing a free reconciliation. So, if forgiveness means the extending of an offer, (2) is false; if forgiveness means reconciliation, (1) is false.

A final move is this: Jesus says: (x)(if x blasphemes the Holy Spirit, then x is not forgiven). As a quantified material conditional, this is trivially true if no one blasphemes the Holy Spirit. Hence, the passage in question does not prove (2)--to prove (2), we would need the additional claim that in fact someone blasphemes the Holy Spirit. Maybe, though, what Jesus says is an entailment: necessarily if x blasphemes the Holy Spirit, then x is not forgiven. But the logical necessitation is not in the text. Or maybe what we have is a subjunctive conditional: (x)(were x to blaspheme the Holy Spirit, x would not be forgiven). But maybe the antecedent is impossible, and so this is either trivially true or else it is a true per impossibile conditional.

The problem with the argument you set forth, in my view, is clearly with premise 1. Why assume that the GCB will forgive all sins? And why assume that "any being that will forgive all sins is greater than one that will not?"

There are several things presupposed by these premises to which I would object. Without getting into all of them, your argument sees to, at the very least, preclude the NT as divine revelation. I say this because there are many NT (as well as OT) Scriptures that explicitly contradict universalism.

Also, the assumption that "any being that will forgive all sins is greater than one that will not" ignores the notion free will, according to which (I think many would agree) one can freely reject God's offer of salvation through Jesus Christ. Is the GCB then on the hook for those who reject forgiveness of sins? But again, implicit is the assumption that divine revelation is not in view here.

But maybe the antecedent is impossible, and so this is either trivially true or else it is a true per impossibile conditional.

Christ utters a warning against doing what is impossible to do? I wonder how many Gricean restrictions that violates. The most plausible line is to take the conditional as strict, I think, and the antecedent as rare but possible. So, (2) is likely true.

Alexander, let's consider how those points can be related to the various versions of Jesus' words that we have.

He could simply have in mind some group of beings who, as a matter of fact, were the only people guilty of blasphemy against the Holy Spirit and who, as a matter of fact, will not be forgiven. This group could even consist of just one member - Satan. Compare this with John 14:26-27, where Jesus says that the one to whom he gives the morsel of bread will betray him. As a matter of fact, the set of people to whom the morsel is given is equivalent to the set of people who will betray Jesus.

If the only version we had was Luke 12v10, it would be plausible to say that Jesus has just one individual in mind: the blasphemer against the Holy Spirit will never be forgiven; but that doesn't fit Mark or Matthew, and I suspect the different phrasing of Luke 12v10 is due to Luke. I don't think it would fit Thomas either (Logion 44), but I've only read that passage in translation.

Just focussing on Mark 3v29, we have the same basic phrasing in 3v35, in both cases "whoever does this" fits as a translation. This is a subjunctive conditional. I don't think that subjunctive conditionals with false or even impossible antecedents are trivially true, but that's hardly relevant here. Even if Jesus thought that such conditionals were trivially true, why on earth would he choose to utter a conditional that he knows to be trivially true at this time? He could just as well have said "Whoever makes a square circle will never be forgiven, whoever breaks the law of non-contradiction will never sin." I cannot read this passage either as a reference to a specific sin that Jesus knew some person or group of people did commit, nor as a reference to a sin he knows will never (and perhaps can never) be committed. They key word in the Greek, for me, is "an". (There may well be people out there with more knowledge of Greek than I have - but so far they haven't said anything).

We also are told that Jesus is saying this because people accuse him of having an unclean spirit - the implication would seem to be that calling the Holy Spirit unclean, as these people have just done, will never be forgiven. However, Mark 3v35 as a whole is contrasting sins of the son of men with whoever blasphemes againt the Holy Spirit, which could be contrasting human sin with angelic sin.

Matthew 12v31 contrasts all blasphemy against the Son of Man with the blasphemy against the Holy Spirit - which could be a reference to one specific act, performed by Satan. However, the following verse, similar in phrasing to Mark 3v35, so again we come back to a subjunctive conditional.

So, I would say we have a subjunctive conditional grounded in knowledge of a necessary connection between this sin and never being forgiven.

I can see why the concept of the impenitent sin seems to fit: what else could be a sin that is, by nature, unforgiveable? However, so far, nobody has addressed the question why Jesus would use the term "blasphemy against the Holy Spirit" to describe such a sin. If I spoke about "blasphemy against Jesus" or "blasphemy against Muhammad" or "blasphemy against Zeus", I think you would have a very good idea what I meant. When I want to tell my students that plagiarism is the worst offence they can commit in class, I tell them just that. I don't tell them that "bringing the university into disrepute" is the worst offence then let them figure out that this means plagiarism. It is only because we can't think of a reason why blasphemy against the Holy Spirit should be unforgiveable that we are starting out by trying to figure out what an unforgiveable offence might be, within the limits of GCB theology, then attributing that to Jesus.

So let me suggest an alternative approach: the prohibition against blasphemy against the Holy Spirit is somewhat like "You can insult me, but not my mother" and perhaps also somewhat like "Don't step on my blue suede shoes" - particularly in Thomas' version:

"Whoever blasphemes against the Father will be forgiven, and whoever blasphemes against the Son will be forgiven, but whoever blasphemes against the Holy Spirit will not be forgiven either on earth or in heaven."

One can understand why Jesus would say "Blaspheme against me, but not other members of the Trinity", but why allow blasphemy even against the Father, but not the Holy Spirit? It seems arbitrary - and hence my comparison with "Don't step on my blue suede shoes." It is an assertive statement precisely because it seems so whimsical. It is the equivalent to my making a rule, in my classes, that nobody can wear a Liverpool FC t-shirt because I say so, but that colours of any other football club are acceptable. It reminds everyone that some rules rest on nothing more than my authority.

This is quite different, I think, from the whole approach of GCB Theology, where it is understood that one can figure out on a priori grounds how God would act, because his actions are always reasonable. An alternative theology would say that God acts in accordance with his own good pleasure, and we must rely on a revealer to know what that good pleasure is. I think that the case Andrew has selected is interesting, because it suggests that Jesus' theology took the latter form.

Ben, you said:

"An alternative theology would say that God acts in accordance with his own good pleasure, and we must rely on a revealer to know what that good pleasure is. I think that the case Andrew has selected is interesting, because it suggests that Jesus' theology took the latter form."

But if one supposes that "God acts in accordance with his own good pleasure," doesn't that present a potential defeater for Andrew's statement that "Regarding (1), it seems to me that any being that will forgive all sins is greater than one that will not."

The greatness of God must then be defined according to God's own good pleasure, instead of supposing greatness, (in this instance), is predicated on the extent of God's forgiveness.

The alternative theology proposed at the end of your last, in my estimation, works against - not in favor of - Andrew's argument.

Let me say that the triviality or per impossibile option is only a last resort, and I think there are better options, which I outlined in my comment.

But let me defend the acceptability of this last resort.

1. Consider this sub-hypothesis: Jesus qua human being does not in fact know whether or not it is possible to commit the sin against the Holy Spirit. But he does know that if the sin were committed, it would not be forgiven. In that case, he can sincerely say that anybody who commits this sin won't be forgiven. And in saying this, he has asserted something true, and need not have violated any Gricean rules (not that it's wrong to violate Gricean rules for good reason). This is compatible with Jesus--even qua human being--being inerrant in speech and belief. So, as long as we allow that there are some linguistically-expressible propositions that Jesus qua human being does not know, this hypothesis can be defended (I am not endorsing the antecedent of this conditional, because I have not surveyed the Patristic data sufficiently).

[This relates to a worry I sometimes have about certain lines of biblical exegesis. One reads a text, and then one tries to figure out what the author must have been thinking, what motivations he might have had for writing this text, and so on. This is all well and good. But I think a distinction has to be made: The biblical author is authoritative in what he asserts in the text (and maybe in some other things--it is a hard task to figure out what authoritativeness in, say, prayers in the Bible), and while what the author was thinking and what motivations he had is relevant to figuring out what proposition he in fact asserted, it does not carry the same authority as what he in fact asserted.]

2. Here is a somewhat preferable defense of the per impossibile hypothesis. Sometimes one can state a per impossibile conditional as a limiting case of ordinary subjunctives whose antecedents approach the impossible antecedent and whose consequents approach the consequent. The sin against the Holy Spirit is the sin of definitively rejecting the Holy Spirit's forgiving activity, or something like that. Maybe it is not possible by a discrete act to do that. But one can do acts that approximate this impossible act, and the closer one gets to the impossible act, the harder it is for the sin to be forgiven. So, one can say that, in the limit, when one has done the impossible act, the forgiveness is also impossible. The warning, then, is not to reject the Holy Spirit's forgiving activity, even non-definitely, because the closer one comes, the harder the forgiveness will be. (Here is a model: The closer one comes to the definitive rejection, the more time one will spend in purgatory. In the limit, one gets an infinite amount of time, and that counts as hell, not purgatory.)

Ben:

On the "why the Holy Spirit" question, I would add that the Holy Spirit is the person of the Trinity most properly said to indwell in the believer. Rejection of the Holy Spirit is thus very intimately tied to rejection of the Christian life.

All that said, I also think it is difficult in general to apply our usual rules of discourse to what Jesus says, apart from the rule that one should not speak falsely. Jesus is quite capable of saying something that is true but that ends up confusing those he is talking with, and there can be a variety of pedagogical purposes this could serve. Irony is quite possible. Standard implicatures are routinely canceled or subverted in Jesus' speech. (Thus, when someone says: "Why do you call me good? No one but God is good", normally we would take this to implicate that the speaker is not good. In Jesus' use of the line, there is irony, but nonetheless the assertion is true.)

Jesus qua human being does not in fact know whether or not it is possible to commit the sin against the Holy Spirit. But he does know that if the sin were committed, it would not be forgiven. In that case, he can sincerely say that anybody who commits this sin won't be forgiven

I don't think he can sincerely say that, since he does know qua omniscient being. So he does know simpliciter whether it is impossible. That is, he could offer the correct answer at any time at which he were asked.

Alexander - I'd be happy to attribute to Jesus a subjunctive conditional that is true despite having an impossible antecedent. I would only object if it were said of this conditional that only the impossibility of the antecedent makes the conditional true, first because I think that impossible antecedents don't automatically make the resulting subjunctives true, secondly because (here follows an example of a subjunctive conditional with what is, in my opinion, an impossible antecedent) if it were the case that subjunctive conditionals with impossible antecedents are trivially true, still it would be misleading for Jesus to state such a conditional, in this case, with no other grounds than that trivial truth.

I agree entirely that it is sometimes no bad thing to break Grice's conversational rules, and that Jesus used devices such as irony for pedagogical and other purposes. However, I think its entirely reasonable to ask why he would have used such devices in this case: what did he want to communicate, to whom, and why in this way? We are, after all, considering whether this passage is a counter-example to Perfect Being Theology. The PB Theologian needs to present a plausible interpretation of the passage.

Gavin - this leads to your point. Certainly, when we have any ideas about why God would deem a certain kind of sin unforgiveable, we can rebuild our idea of God's greatness around that idea, thus preserving the idea that Jesus' conception of God was the GCB. However, I'm supposing that Perfect Being Theology is not merely having the belief that God is the GCB, but that it involves the view that one can derive from that idea alone substantive ideas about God's nature, attributes and actions. So it is in keeping with that approach that one would be able to derive from the concept of God's greatness the kind of sin that he would never forgive. Whereas the rival approach is to say that God is the Greatest Conceivable Being, but that fact alone does not explain why he would select blasphemy against the Holy Spirit as the unforgiveable sin, thus revealing a limitation of a particular theological method.

All that said, I also think it is difficult in general to apply our usual rules of discourse to what Jesus says, apart from the rule that one should not speak falsely.

"My God, My God, why have you forsaken me?" is strictly speaking a question and not an assertion, but it does conversationally imply "God has forsaken me," doesn't it? And the things Alex says about irony and parables etc. seem not to apply here.

This is wandering off into theology, and I'm sure that this passage has been extensively discussed (a discussion I'm not familiar with). But if you think that God didn't forsake Jesus, then Matthew seems to depict Jesus as at least implying something false.

Tim:

Prior to the advent of chapter and verse numbering, a standard Jewish way to refer to a text of Scripture is by giving its beginning, such as the first few words of a verse, or the first line. A standard interpretation of Jesus' words is that he, in fact, recited the whole Psalm. And in the context of the Psalm as a whole it is clear that the author is not, in fact, abandoned.

In any case, implicature takes into account the addressee. The addressee here is God, not us. (The point is underscored by the fact that the people around Jesus tend to mishear--they think he is calling on Elijah.) There is no Gricean obligation to speak in such ways as to be useful to those who aren't party to the conversation. If Christ and God both know, and each know that they both know, that God hasn't literally abandoned Christ, then there is no implicature that God has done so, but the question must play a different sort of conversational role. Perhaps Christ is asking why it feels like God has abandoned him. Perhaps Christ is identifying with all foresaken people throughout history and speaking on their behalf. Perhaps all of the above.

Dear Andrew,

To properly understand this scripture, we need to understand that many words we read in many bibles today are not always translated correctly. Like in this passage.

Let's look at the keyword that causes confusion and makes us believe that there are sins that can never (for all eternity) be forgiven.

The word aion. This is translated as 'eternal' or 'for ever' or in this case 'never'. The word aion properly translated means an 'age' or 'period of time', how ever long this may be. It definitely does not mean 'time without end'.

Look at the passage from the Young's Literal Translation:

Mar 3:28 `Verily I say to you, that all the sins shall be forgiven to the sons of men, and evil speakings with which they might speak evil,
Mar 3:29 but whoever may speak evil in regard to the Holy Spirit hath not forgiveness--to the age, but is in danger of age-during judgment;'

No 'for evers' and no 'eternal punishment'. It helps to better know the scriptures, then we can not easily be misled or deceived.

I think you have to tease out precisely what you mean by "forgive". In your last example - a parent forgiving a child - forgiveness clearly seems something different than what we believe God does.

There are two understood definitions of forgiveness:

1) A cancellation of punishment regardless of personal feeling.
2) A release of bitter personal feeling regardless of punishment.

According to my somewhat limited understanding of Biblical history, language, and terminology, the definition used in Biblical times was the first definition. Originally, the word for forgiveness meant that punishment went away and it had absolutely NOTHING to do with feelings. The second definition was developed later by the Church.

This second definition developed by the Church is often viewed as a false definition...something of a misunderstanding of forgiveness.

According to the second "false" definition, a mother could release her feelings of anger and resentment towards a child and still punish him, thereby both forgiving and punishing him.

According to the first original definition (the definition that Jesus and those in His culture would have used) a mother could not both cancel punishment and then still punish her child...that would obviously be a contradiction, so it would be impossible for a mother to both forgive and punish her child.

Andrew, this is why so many people have requested your definition: because the two definitions are opposites in a way, and so the argument cannot truly be analyzed until a definition of forgiveness is chosen. I think until then, commenters will continue to talk past each other and misunderstand each other as a result of assuming opposing definitions. (Two parties cannot reach a conclusion when they are using different definitions of the central concept.)

On a sidenote, I found an article reqarding Mark 3:28-29, which makes an interesting argument that the passage itself actually proves that forgiveness requires repentence: http://www.darryljsmith.com/pastortom/wordpress/?p=167

I do not agree that one must repent in order to be forgiven. First think about a guy called Jake that does something to harm John, so that Jake is guilty and will remain unforgiven until John forgives him.
But if Jake dies the next day after harming John and does not get the chance to repent, it follows that John cannot forgive Jake because Jake did not repent.
Or consider another situation where we do a sin without knowing that we did that particularly sin. But if we don't repent it follows God could not forgive us, that entails that for every sin that we did without knowing that we are doing a sin, we will not be forgiven.
But I think you would agree with me that John can forgive Jake and that God can forgive people for sins they are unaware of doing.

Regarding your argument Andrew I have the intuition that it might be impossible to God to forgive this sin, because it is an eternal sin. I will try to present an analogy to show why.
Consider we have to cups, cup A and cup B, than consider there is a tap above cup B. Cup A represents the cup that holds the forgiven sins, cup B the unforgiven sins, the tap represents the way by which sins come to be and the sins are represented by water that drops or flows from the tap into cup B. Every time we sin the tap opens for a brief period of time (depending on how great the sin is) and water flows from the tap into cup B. But every time there is water in cup B, God can come and take it and put it in cup A.
But when someone does an eternal sin, he makes the equivalent of letting the tap opened forever. God can come and take water from cup B and put it in cup A, but there will always be water left in cup B because the tap that brings the water in cup B remains open forever.

I am not sure that this works as an argument that it is impossible to forgive an eternal sin, but if it does, than I believe that the GCB cannot forgive this sin (that is an eternal one) and your argument fails.

P.S. Please excuse my English, I am not a native English speaker nor a professional philosopher so I might have done some serious mistakes.

DI:

"Or consider another situation where we do a sin without knowing that we did that particularly sin. But if we don't repent it follows God could not forgive us, that entails that for every sin that we did without knowing that we are doing a sin, we will not be forgiven."

We can repent in general terms: "I hereby repent for all the sins I can no longer remember, resolving to avoid all sin."

I also don't know that it is possible to culpably commit a sin without knowing one is doing wrong. If it's impossible, then the issue of forgiveness is moot in the case of sins committed unknowingly, because we are not culpable there. (But that still leaves the question of those sins that one has committed but forgotten about, which one needs to repent of in general terms.)