Ablution of the Hands
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Exodus 30:18–21
“You are to make a bronze basin with a bronze stand for washing. Set it between the Tent of Meeting and the altar, and put water in it, / with which Aaron and his sons are to wash their hands and feet. / Whenever they enter the Tent of Meeting or approach the altar to minister by presenting an offering made by fire to the LORD, they must wash with water so that they will not die.
Exodus 40:30–32
He placed the basin between the Tent of Meeting and the altar and put water in it for washing; / and from it Moses, Aaron, and his sons washed their hands and feet. / They washed whenever they entered the Tent of Meeting or approached the altar, just as the LORD had commanded Moses.