Exodus 30:18-21

¹⁸"You shall also make a basin of brass, and the base of it of brass, in which to wash. You shall put it between the tent of meeting and the altar, and you shall put water in it. ¹⁹Aaron and his sons shall wash their hands and their feet in it. ²⁰When they go into the tent of meeting, they shall wash with water, that they not die; or when they come near to the altar to minister, to burn an offering made by fire to Yahweh. ²¹So they shall wash their hands and their feet, that they not die: and it shall be a statute forever to them, even to him and to his descendants throughout their generations."