Exodus 30:19-21

¹⁹Aaron and his sons shall wash their hands and their feet from it; ²⁰when they enter the tent of meeting, they shall wash with water, so that they will 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 will not die; and it shall be a perpetual statute for them, for Aaron and his descendants throughout their generations.”