Exodus 30:18-21

¹⁸"You shall also make a laver of bronze, with its base of bronze, for washing. And you shall put it between the tent of meeting and the altar, and you shall put water in it, ¹⁹with which Aaron and his sons shall wash their hands and their feet. ²⁰When they go into the tent of meeting, or when they come near the altar to minister, to burn an offering by fire to the LORD, they shall wash with water, lest they die. ²¹They shall wash their hands and their feet, lest they die: it shall be a statute for ever to them, even to him and to his descendants throughout their generations."