Leviticus 8:2

“You shall put them on Aaron your brother and on his sons with him; and you shall anoint them and ordain them and set them apart as holy, that they may minister to Me as priests.

“Now this is what you shall do to them to set them apart as holy to minister as priests to Me: take one bull from the herd and two rams without blemish,

“You shall gird them with sashes, Aaron and his sons, and bind caps on them, and they shall have the priesthood by a perpetual statute. So you shall ordain Aaron and his sons.

“Then you shall bring Aaron and his sons to the doorway of the tent of meeting and wash them with water.

Moses then took the anointing oil and anointed the tabernacle and all that was in it and set them apart as holy.

Then he brought near the ram of the burnt offering, and Aaron and his sons laid their hands on the head of the ram.

Then he brought near the second ram, the ram of ordination, and Aaron and his sons laid their hands on the head of the ram.

Moses and Aaron were among His priests, And Samuel was among those who called on His name; They would call upon Yahweh and He would answer them.