Proverbs 6:32

But whoso committeth adultery with a woman lacketh understanding: he that doeth it destroyeth his own soul.

Whoever commits adultery lacks understanding and destroys his own soul, bringing destruction upon himself. Sin grows out of refusing wisdom and instruction, for to break spiritual law is to bring spiritual disease and death. The path of wisdom is the path of life, while to reject reproof is to have life ruined by sin. Because the soul is thus destroyed by such doing, the soul can be destroyed and is not immortal.