Every one of our sinful actions has a suicidal power on the faculties that put that action forth. When you sin with the mind, that sin shrivels the rationality. When you sin with the heart or the emotions, that sin shrivels the emotions. When you sin with the will, that sin destroys and dissolves your willpower and your self-control. Sin is the suicidal action of the self against itself. Sin destroys freedom because sin is an enslaving power.
Timothy J. Keller
sin