“And forgive us our trespasses, as we forgive those who trespass against us”
“After supply of food, next pardon of sin is asked for, that he who is fed of God may live in God, and not only the present and passing life be provided for, but the eternal also; whereunto we may come, if we receive the pardon of our sins, to which the Lord gives the name of debts (Matt 18:32). . . . How well is it for our need, how provident and saving a thing, to be reminded that we are sinners compelled to make petition for our offences, so that in claiming God’s indulgence, the mind is recalled to a recollection of its guilt. That no man may plume himself with the pretence of innocence, and perish more wretchedly through self-exaltation, he is instructed that he commits sin every day by being commanded to pray for his sins.” -St. Cyprian of Carthage
“In thus bidding the faithful pray for forgiveness of sin, He shows that even after baptism sin can be remitted.” -St. John Chrysostom
“That good which in our penitence we ask of God, we should first turn and bestow on our neighbour.” -St. Gregory the Great
“He wishes, if I may so speak, to make God the imitator of the patience which men practise, that the kindness which they have shown to their fellow servants, they should in like manner seek to receive in equal balance from God, who recompenses to each man justly, and knows how to have mercy upon all men.” -St. Cyril of Alexandria
“Whereas we are bound to render unto Christ all manner of holiness, who maketh His Spirit to dwell in us, we are to be blamed if we keep not our temples clean for Him. But this defect is supplied by the goodness of God, remitting to human frailty the severe punishment of sin. And this act is done justly by the just God, when we forgive as it were our debtors, those, namely, who have injured us, and have not restored what was due.” -Titus of Bostra
Quotations from St. Thomas Aquinas, Catena Aurea: Commentary on the Four Gospels Collected Out of the Works of the Fathers, Vols. I and III (Oxford: John Henry Parker, 1841-43).