God spoke to Moses:
"Make a bronze Washbasin; make it with a bronze base. Place it between the Tent of Meeting and the Altar. Put water in it.
Aaron and his sons will wash their hands and feet in it.
When they enter the Tent of Meeting or approach the Altar to serve there or offer gift offerings to God, they are to wash so they will not die.
They are to wash their hands and their feet so they will not die. This is the rule forever, for Aaron and his sons down through the generations." Holy Anointing Oil