Deuteronomy 23:13

And thou shalt have a place outside of the camp, and thou shalt go out thither,

And thou shalt have a paddle upon thy weapon; and it shall be, when thou wilt ease thyself abroad, thou shalt dig therewith, and shalt turn back and cover that which cometh from thee:

You shall have a trowel among your weapons. It shall be, when you relieve yourself, you shall dig with it, and shall turn back and cover your excrement;