The grounds of forgiveness -
Can anyone give me a good answer to this question: On what grounds does God forgive sin?
I'm particularly curious as to how people were forgiven in the Old Testament, and before Christ's death. Evangelicals will often say that God only forgives us because of Christ's sacrifice. But then on what grounds is Christ able to teach his disciples "...if you forgive men when they sin against you, your heavenly Father will also forgive you..."? Matt. 6:14.
One idea I've heard is that of forbearance - that God basically reserved judgment until Christ died, sort of so that Christ's sacrifice could be applied retroactively. Maybe, but this kind of strains the text of the Lord's prayer, and numerous places in the OT when it says that God forgives people their sins. (E.g. Psalm 130:3-4 "If you, O Lord, kept a record of sins, O Lord, who could stand? But with you there is forgiveness; therefore you are feared.")