He who immerses himself in sexual intercourse will be assailed by premature aging, his strength will wane, his eyes will weaken, and a bad odour will emit from his mouth and his armpits, his teeth will fall out and many other maladies will afflict him.
MaimonidesOne should see the world, and see himself as a scale with an equal balance of good and evil. When he does one good deed the scale is tipped to the good - he and the world is saved. When he does one evil deed the scale is tipped to the bad - he and the world is destroyed.
Maimonides