Edwards on Repentance

"Though [repentance] be a deep sorrow for sin that God requires as necessary to salvation, yet the very nature of it necessarily implies delight. Repentance of sin is a sorrow arising from the sight of God's excellency and mercy, but the apprehension of excellency or mercy must necessarily and unavoidably beget pleasure in the mind of the beholder. 'Tis impossible that anyone should see anything that appears to him excellent and not behold it with pleasure, and it's impossible to be affected with the mercy and love of God, and his willingness to be merciful to us and love us, and not be affected with pleasure at the thoughts of [it]; but this is the very affection that begets true repentance. How much sovever of a paradox it may seem, it is true that repentance is a sweet sorrow, so that the more of this sorrow, the more pleasure."

From The Pleasantness of Religion (1723), published in The Sermons of Jonathan Edwards: A Reader.