In ancient Israel, when a decision of national significance was needed, the High Priest was consulted. Within the fold of the High Priest’s breastplate were the Urim and Thummim (lights and perfections).1 According to most traditions, the Urim and Thummim were a piece of parchment with G‑d’s four-letter name written on it.2 Its function was to serve as an oracle, divining whether or not the Jewish people should take a certain course of action,3 and was to be used only by the king, the Jewish high court, or a person needed by the whole community4 such as a general.5

When its services were needed, the Kohen Gadol would stand facing the Holy Ark with the questioner behind him. The individual desiring an answer would ask a simple yes-or-no question such as, “Shall we go to war?” The Kohen Gadol would meditate until he reached Divine inspiration. Then, certain letters on the breastplate (upon which the names of the twelve tribes were written) would appear to protrude6 or light up,7 producing an answer.8

The Urim and Thummim were lost after the destruction of the First Temple.9 According to another tradition, it was extant but ceased to work.10