Originally Posted by Carn

MASTURBATION IN ITSELF IS NOT A SIN. You don't have to repent for it. However, if you think about a man/woman (who is not your husband/wife, even if you aren't married yet) while you wank, THAT is a sin. Lusting is a sin, and coveting another person's spouse is a sin, but the Bible says NOTHING about masturbation being a sin.