Mortal sin is like a bomb blast: the damage to one’s soul is immediate and catastrophic.

Venial sin is like a termite infestation. It may not seem like much at first, but if you don’t deal with it quickly and decisively, that one or two wee little bugs you almost don’t even notice are going to multiply, and become a colony; and that colony has the capability of doing some serious long-term damage to the structure it inhabits: your soul.