It is ingrained in all living creatures, first of all, to preserve their own safety, to guard against what is harmful, to strive for what is advantageous.
Ambrose... the Lord Jesus said, 'To those who are in bonds, Come out, and to those who are in prison, Go forth' (Isa. 49:9); so your sins are forgiven. All, then, are forgiven, nor is there any one whom He has not loosed. For thus it is written, that He has forgiven 'all transgressions, doing away with the handwriting of the ordinance that was against us' (Col. 2:13-14). Why, then, do we hold the bonds of others, while we enjoy our own remission? He, who forgave all, required of all that what every one remembers to have been forgiven to himself, he also should forgive others.
Ambrose