2. Offence is removed only by love.* But by mortal sin man quarrels with God: for it is said that God 'hates' sinners, inasmuch as He is minded to deprive them of the last end, which He has in preparation for them who love Him. Man then cannot rise from sin except by grace, whereby friendship is established between God and man.
Hence it is said: It is I who blot out thine iniquities for my own sake (Isai. xliii, 25).
Hereby is refuted the error of the Pelagians, who said that man can rise from sin by free will.
3.157 : That he who falls from Grace by Sin may be recovered again by Grace
3.159 : How Man is delivered from Sin