Exodus 30:18-21

18“You shall also make 1a basin of 2bronze, with its base of bronze, for washing; and you shall 3put it between the tent of meeting and the altar, and you shall put water in it. 19Aaron and his sons shall 4wash their hands and their feet from it; 20when they enter the tent of meeting, they shall wash with water, so that they do not die; or when they approach the altar to minister, by offering up in smoke a fire sacrifice to the Lord. 21So they shall wash their hands and their feet, so that they do not die; and 5it shall be a permanent statute for them, for 6Aaron and his 7descendants throughout their generations.”