We believe that God forgives us our sins; but also that He will not do so unless we forgive other people their sins against us. There is no doubt about the second part of this statement. It is in the Lord's Prayer, it was emphatically stated by our Lord. If you don't forgive you will not be forgiven. No exceptions to it. He doesn't say that we are to forgive other people's sins, provided they are not too frightful, or provided there are extenuating circumstances, or anything of that sort. We are to forgive them all, however spiteful, however mean, however often they are repeated. If we don't we shall be forgiven none of our own.
Now it seems to me that we often make a mistake both about God's forgiveness of our sins and about the forgiveness we are told to offer to other people's sins. Take it first about God's forgiveness, I find that when I think I am asking God to forgive me I am often in reality (unless I watch myself very carefully) asking Him to do something quite different. I am asking him not to forgive me but to excuse me. But there is all the difference in the world between forgiving and excusing. Forgiveness says, "Yes, you have done this thing,