Exodus 29:1-4

1And this is the thing that thou shalt do to them to hallow them, to minister to me in the priest’s office: Take one young bull, and two rams without blemish,

2And unleavened bread, and cakes unleavened tempered with oil, and wafers unleavened anointed with oil: of wheat flour shalt thou make them.

3And thou shalt put them into one basket, and bring them in the basket, with the bull and the two rams.

4And Aaron and his sons thou shalt bring to the door of the tabernacle of the congregation, and shalt wash them with water.