13 Let us therefore say every day; and say it in sincerity of heart, and do what we say, “Forgive us our debts, as we also forgive our debtors.” It is an engagement, a covenant, an agreement that we make with God. The Lord your God says to you, Forgive, and I will forgive. You have not forgiven; you retain your sins against yourself, not I. I pray you, my dearly beloved children, since I know what is expedient for you in the Lord's Prayer, and most of all in that sentence of it, “Forgive us our debts, as we also forgive our debtors;” hear me. You are about to be baptized, forgive everything; whatsoever any man have in his heart against any other, let him from his heart forgive it. So enter in, and be sure, that all your sins which you have contracted, whether from your birth of your parents after Adam with original sin, for which sins' sake ye run with babes to the Saviour's grace, or whatever after sins you have contracted in your lives, by word, or deed, or thought, all are forgiven; and you will go out of the water as from before the presence of your Lord, with the sure discharge of all debts.
Source: Sermons on Selected Lessons of the New Testament (New Advent)