Deuteronomy 23:10-15

10If there is someone among you who is impure because of some nocturnal emission, he must leave the camp; he may not reenter it immediately.

11When evening arrives he must wash himself with water and then at sunset he may reenter the camp.

12You are to have a place outside the camp to serve as a latrine.

13You must have a spade among your other equipment and when you relieve yourself outside you must dig a hole with the spade and then turn and cover your excrement.

14For the Lord your God walks about in the middle of your camp to deliver you and defeat your enemies for you. Therefore your camp should be holy, so that he does not see anything indecent among you and turn away from you.

15You must not return an escaped slave to his master when he has run away to you.