Deuteronomy 23:10
If there shall be in thee a man that shall not be clean from chance of the night, and he shall go forth without the camp; he shall not come in to the midst of the camp:
Leviticus 15:16
And a man, when the effusion of seed shall go forth from him, and he washed in water all his flesh, and was unclean till the evening
Numbers 5:2-3
Command the sons of Israel, and they shall send forth from the camp every one leprous, and every one flowing, and every one unclean for the soul:
1 Corinthians 5:11-13
And now I wrote to you not to mix together, if any called a brother is a fornicator, or covetous, or an idolater, or a railer, or intoxicated, or rapacious; not to eat with such.