28:30 “You are to put the Urim and the Thummim40 into the breastpiece of decision; and they are to be over Aaron’s heart when he goes in before the Lord. Aaron is to bear the decisions41 of the Israelites over his heart before the Lord continually.
snThe Urim and the Thummim were two objects intended for determining the divine will. There is no clear evidence of their size or shape or the material of which they were made, but they seem to have been familiar items to Moses and the people. The best example of their use comes from 1 Sam 14:36–42. Some have suggested from the etymologies that they were light and dark objects respectively, perhaps stones or sticks or some other object. They seem to have fallen out of use after the Davidic period when the prophetic oracles became popular. It may be that the title “breastpiece of judgment” indicates that these objects were used for making “decisions” (J. P. Hyatt, Exodus [NCBC], 283–84). U. Cassuto has the most thorough treatment of the subject (Exodus, 378–82); he lists several very clear rules for their uses gathered from their instances in the Bible, including that they were a form of sacred lot, that priests or leaders of the people only could use them, and that they were used for discovering the divine will in areas that were beyond human knowledge.
41
tn Or “judgment” (KJV, ASV, NASB, NRSV). The term is מִשְׁפָּט (mishpat), the same word that describes the breastpiece that held the two objects. Here it is translated “decisions” since the Urim and Thummim contained in the breastpiece represented the means by which the Lord made decisions for the Israelites. The high priest bore the responsibility of discerning the divine will on matters of national importance.