Exodus 28 and 29 deal with the priestly garments and the sacrifices associated with consecrating the priests. It isn’t super inspiring, although here is a passage that seemed interesting.
27 “Consecrate those parts of the ordination ram that belong to Aaron and his sons: the breast that was waved and the thigh that was presented. 28 This is always to be the perpetual share from the Israelites for Aaron and his sons. It is the contribution the Israelites are to make to the Lord from their fellowship offerings. . . . 31 “Take the ram for the ordination and cook the meat in a sacred place. 32 At the entrance to the tent of meeting, Aaron and his sons are to eat the meat of the ram and the bread that is in the basket. 33 They are to eat these offerings by which atonement was made for their ordination and consecration. But no one else may eat them, because they are sacred.
Professional clergy. When societies were deciding what required specialization, connecting with the divine was an early choice. I wonder if connecting with the divine can be fairly linked to individual spirituality. Did the former give rise to the latter?
As for interesting stuff, here’s something crazy. With all of the details in this passage, the colors are not the same in my English and Spanish translations. Throughout chapter 28, stuff is supposed to be made of “gold, and blue, purple and scarlet yarn, and fine linen.” But, in Spanish this is rendered as “oro, púrpura, carmesí, escarlata y lino.” Since purple and scarlet are in both, I assumed carmesi was a shade of azul. No es verdad. carmesi is basically crimson. So, which is it!
One final deep dive–Urim & Thummim are used by priests to make decisions, but no one seems to know what they look like or exactly what they are. No one meaning no one whose material has been collected by Wikipedia.