God is gracious for no reason outside of himself. Whatever it is that drives his desire to forgive sinners is imbedded somewhere within his being and it isn’t for us to understand. At least not now, not fully.

God forgives to satisfy his desire to forgive. It is as William Gurnall describes:

You know the reason why God stands so long waiting on sinners, months, years, preaching to them; it is that He may be gracious in pardoning them, and in that act delight himself. Princes very often pardon traitors to please others more than themselves, or else it would never be done but God doth it chiefly to delight and glad His own merciful heart. Hence the business Christ came about (which is no other but to reconcile  sinners to God) is called “the pleasure of the Lord.”

I discover profound encouragement knowing that God has forgiven my sins because it pleases him, and not because I have in some way convinced him to do so.