Urim and Thummim

The Urim and Thummim (Hebrew: lights and perfections) were objects kept in the high priest's breastplate and used to receive divine guidance on specific questions, particularly in matters of national decision (Ex. 28:30; Lev. 8:8). Their precise nature is unknown — ancient and modern scholars have proposed various theories including lots, gemstones that changed appearance, or oracle-mechanisms. Their function appears to have been binary (yes/no), as when Saul inquired about pursuing the Philistines and received no answer (1 Sam. 14:37, 41; 28:6).

The Urim is explicitly mentioned as the medium of priestly inquiry in Numbers 27:21, where Joshua is to stand before Eleazar the priest who shall inquire for him by the judgment of the Urim. After the First Temple period, the Urim and Thummim apparently ceased functioning; the post-exilic community knew they were needed to settle questions of priestly lineage but had none available (Ezra 2:63; Neh. 7:65). No reference to them appears in the NT.