Cur Deus Homo, II-XV
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Cur Deus Homo
How this death removes even the sins of his murderers.
Boso. This is properly so with regard to all sins not affecting the person of the Deity. But let me ask you one thing more. If it be as great an evil to slay him as his life is a good, how can his death overcome and destroy the sins of those who slew him? Or, if it destroys the sin of any one of them, how can it not also destroy any sin committed by other men? For we believe that many men will be saved, and a vast many will not be saved.
Anselm. The Apostle answers the question when he says: "Had they known it, they would never have crucified the Lord of glory." For a sin knowingly committed and a sin done ignorantly are so different that an evil which they could never do, were its full extent known, may be pardonable when done in ignorance. For no man could ever, knowingly at least, slay the Lord; and, therefore, those who did it in ignorance did not rush into that transcendental crime with which none others can be compared. For this crime, the magnitude of which we have been considering as equal to the worth of his life, we have not looked at as having been ignorantly done, but knowingly; a thing which no man ever did or could do.
Boso. You have reasonably shown that the murderers of Christ can obtain pardon for their sin.
Anselm. What more do you ask? For now you, see how reason of necessity shows that the celestial state must be made up from men, and that this can only be by the forgiveness of sins, which man can never have but by man, who must be at the same time Divine, and reconcile sinners to God by his own death. Therefore have we clearly found that Christ, whom we confess to be both God and man, died for us; and, when this is known beyond all doubt, all things which he says of himself must be acknowledged as true, for God cannot lie, and all he does must be received as wisely done, though we do not understand the reason of it.
Boso. What you say is true; and I do not for a moment doubt that his words are true, and all that he does reasonable. But I ask this in order that you may disclose to me, in their true rationality, those things in Christian faith which seem to infidels improper or impossible; and this, not to strengthen me in the faith, but to gratify one already confirmed by the knowledge of the truth itself.