Deuteronomy 23:10-14

10“When you go out as an army camp against your enemies, you are to guard yourself from every evil thing.

11If there is among you a man who is not clean from a nighttime emission, he is to go outside the camp—he may not reenter the camp.

12Now toward evening he is to bathe in water, and when the sun sets, he may reenter the camp.

13There is to be a place at hand for you outside the camp, and you are to go there outside.

14You are to have a shovel for yourself among your weapons. Now when you sit down outside, you are to dig with it and turn and cover up what comes out of you.