Exodus 29:1-2

This is the thing that thou shalt do unto them to hallow them— The consecration or setting apart of Aaron and his sons for the priest's office, with its various and solemn ceremonies, is described in this chapter. The providing the animals, &c. for sacrifice, is enjoined first, that they might be in readiness; though several things were to be done previous to the sacrifices themselves. Of these we shall speak in their order. See Leviticus 8. They are to provide for the sacrifice, (Exodus 29:2.) 1st, bread simply unleavened; 2nd, bread unleavened, tempered or mixed with oil; and, 3rdly, bread unleavened, but anointed or covered over with oil after the baking: but what was the reason of this distinction, we presume not to guess.