Deuteronomy 23:12-14

12You are to have a place outside the camp and go there to relieve yourself.

13You are to have a digging tool in your equipment; when you relieve yourself, dig a hole with it and cover up your excrement.

14For the Lord your God walks throughout your camp to protect you and deliver your enemies to you; so your encampments must be holy. He must not see anything indecent among you or he will turn away from you.