Deuteronomy 23:10
When there is in thee a man who is not clean, from an accident at night -- then he hath gone out unto the outside of the camp -- he doth not come in unto the midst of the camp --
Leviticus 15:16
'And when a man's seed of copulation goeth out from him, then he hath bathed with water all his flesh, and been unclean till the evening.
Numbers 5:2-3
'Command the sons of Israel, and they send out of the camp every leper, and every one with an issue, and every one defiled by a body;
1 Corinthians 5:11-13
and now, I did write to you not to keep company with him, if any one, being named a brother, may be a whoremonger, or covetous, or an idolater, or a railer, or a drunkard, or an extortioner -- with such a one not even to eat together;