Exodus 29:1-2

The Consecration of Aaron and His Sons

29:1 “Now this is what you are to do for them to consecrate them so that they may minister as my priests. Take a young bull and two rams without blemish; 29:2 and bread made without yeast, and perforated cakes without yeast mixed with oil, and wafers without yeast spread with oil – you are to make them using fine wheat flour.

Hebrews 7:27

7:27 He has no need to do every day what those priests do, to offer sacrifices first for their own sins and then for the sins of the people, since he did this in offering himself once for all.