Deuteronomy 23:9-14

“When you are encamped against your enemies, then you shall keep yourself from every evil thing. “If any man among you becomes unclean because of a nocturnal emission, then he shall go outside the camp. He shall not come inside the camp, but when evening comes, he shall bathe himself in water, and as the sun sets, he may come inside the camp. “You shall have a place outside the camp, and you shall go out to it. And you shall have a trowel with your tools, and when you sit down outside, you shall dig a hole with it and turn back and cover up your excrement. Because the LORD your God walks in the midst of your camp, to deliver you and to give up your enemies before you, therefore your camp must be holy, so that he may not see anything indecent among you and turn away from you.