One of the more mysterious expressions a Bible reader may encounter is “the Urim and the Thummim” (Exod 28:30; Lev 8:8; Deut 33:8 [in reverse order]; Ezra 2:63; Neh 7:65). In fact, “Urim” and “Thummim” are not translations, but are rather transliterations of Hebrew words whose referent is disputed. If you have heard anything at all about the Urim and the Thummim, chances are good that you have heard one of several theories invented by modern scholars, without support from the Bible or ancient Jewish tradition.
Marginal notes in English Bibles translate the word “Urim” (אוּרִים) as “Lights,” although the plural of the common Hebrew word for light (אוֹר) is slightly different (אוֹרִים = “Orim”). By its form, Urim is the plural of the Hebrew word for “firelight” (אוּר), which is used in the plural form “Urim” in Isaiah 24:15 to refer to the east as the region of the fiery light of the rising sun. While some suggest that “Urim” and “Thummim” are each to be understood as an intensive plural which refers to a single object, Hebrew grammars question whether the intensive plural can be used of non-living things (IBHS §7.4.3; Joüon §136f), and in any case it is not necessary to interpret “Urim” and “Thummim” as intensives. Thus, “Urim” is best understood to mean “the fire-like lights” or “the ones shining like firelight.”
“Thummim” is, to begin with, an inaccurate transliteration of the Hebrew word תֻּמִּים, in which the תּ is given a hard pronunciation; “Tummim” would be a more accurate transliteration, although convention now demands the spelling “Thummim.” Marginal notes in English Bibles translate the word “Thummim” as “Perfections,” although this translation does not seem like the right one for the Hebrew word that is used. (The translation of “Urim” and “Thummim” in the marginal notes of English Bibles as “lights” and “perfections” is evidently taken from the LXX text of Ezra 2:63.) “Thummim” is the plural form of the Hebrew word תֹּם, which occurs in the singular twenty-three times in the Old Testament. This word is usually translated as “integrity” (e.g., 1 Kgs 9:4; Job 4:6; Pss 26:1; 78:72; Prov 2:7), but also can be translated as “innocence” (Gen 20:5-6; 2 Sam 15:11; 1 Kgs 22:34; 2 Chr 18:33) or “completeness” (Job 21:23; Isa 47:9). Translating “Thummim” as “the blameless ones” seems to fit best with basic meaning of the word.
“Urim” and “Thummim” were names given to physical objects that were part of the high priest’s sacred garments. (Compare Solomon’s naming of the two main pillars of the temple porch as “Jachin” and “Boaz” in 1 Kings 7:21.) The high priest’s garment (called an ephod) contained shoulder pieces with two special onyx(?) stones set in sockets of gold (Exod 28:7-14). These stones were engraved with the names of the twelve tribes of Israel—six on one stone, and six on the other. The shoulder pieces were attached to the breastplate, a nine-inch square piece of heavy (double-thick) fabric with four rows of three gemstones set in sockets of gold (Exod 28:15-21). Each gemstone was engraved with the name of one of the twelve tribes (presumably naming Ephraim and Manasseh separately, and excluding Levi, which was represented by the high priest). The breastplate was hung from the shoulder pieces by means of gold chains that were connected to the sockets of the onyx stones on the shoulder pieces (Exod 28:22-25). The Urim and the Thummim are said in Exodus 28:30 to be set into the breastplate (literally, “and you shall set into the breastplate of judgment the Urim and the Thummim”; Leviticus 8:8 also reads “he set into the breastplate the Urim and the Thummim”). This evidently refers to the placement of the gemstones in their gold settings. The Urim and the Thummim seem to be identified in Exodus 28:29-30 with the gemstones which were engraved with the names of the tribes of Israel. The high priest’s breastplate is called “the breastplate of judgment” (Exod 28:15), since God revealed His judgments/decisions to the Israelites through the Urim and the Thummim on the breastplate. The Urim and the Thummim are evidently to be identified with the priest’s ephod that David would often use to inquire, when he seemed to receive audible responses (1 Sam 23:6-12; 30:7-8). The word “ephod” refers to a linen garment, but can refer specifically to the breastplate on the garment that was used for inquiring of God—or, in some instances, for an object used for pagan divination (as in Judg 8:24-27; 17:5).
The most common scholarly interpretation of the Urim and Thummin since the nineteenth century has been to view them as a lot oracle. Scholars have hypothesized various ways in which this might work. One common form of the theory is that the Urim and the Thummim were two stones of similar size and shape that were placed in a pouch behind the breastplate of the high priest. One of these stones (the lighter colored Urim?) signified “Yes” (כֵּן), while the other (the darker colored Thummim?) signified “No” (לֹא). These stones could be used to obtain answers from God to Yes/No questions. When a question was asked, the priest would reach into his breastplate, shake the stones around, and, without looking, pull out one of the two stones. One problem with this theory is that “Urim” and “Thummim” are both plural forms, and so should refer to more than one stone. More importantly, the Bible never describes a pouch behind the high priest’s breastplate with stones in it; the Urim and the Thummim are identified with the stones set in the front of the high priest’s breastplate. This theory also cannot explain how one could fail to receive a response by Urim, as Saul did twice (1 Sam 14:36-37; 28:6). The Urim and the Thummim were different from the practice of casting lots, and their use should not be assumed in passages where the casting of lots is described (e.g., Josh 18:10; 1 Sam 14:41-42; 1 Chr 24:5). (Working on the assumption that the Urim and the Thummim were a lot oracle, many modern translations, including the ESV, NET, NIV, NRSV, RSV, and TNIV, abandon the Hebrew text of 1 Samuel 14:41 in favor of an LXX expansion which explicitly supports the “lot oracle” theory.)
The earliest ancient extrabiblical sources which describe the Urim and the Thummim describe a supernatural illumination of one or more of the stones in the high priest’s breastplate. Josephus (Ant. 3.8.9 §§214-18, available here; search within the page for “I will now treat”) describes how the sardonyx stone on the right shoulder piece of the high priest’s vestments would shine brilliantly when sacrifices were offered (on the Day of Atonement?), in order to indicate that God had accepted the sacrifice (if indeed He had accepted the sacrifice). Josephus also claims that the twelve gemstones in the high priest’s breastplate would shine brilliantly when the people of Israel marched out to battle, in order to signify that God was present with them and had accepted their prayer for victory (if God indeed had accepted their prayer for victory). Josephus’ claim fits with the meaning of the term “Urim” as “fire-like lights.” Josephus also states that the gemstones in the high priest’s breastplate were to be used to inquire of God, and he seems to imply that the stones would illuminate in response to an inquiry (Ant. 4.8.46 §311, available here; search within the page for “Moses taught”).
The Urim are mentioned in 4Q376 (= 1Q29 = 4Q375?), one of the so-called “Dead Sea Scrolls” from Qumran. The text is very fragmentary, so it may very well have mentioned the Thummim also. After the mention of the Urim, the text describes the alternate shining of the stones on the right and left shoulder pieces of the high priest’s ephod at some national feast (the Day of Atonement?). The stones are said to contain “flashes of fire” and to “shine forth” to all the assembled people “until the priest finishes speaking.” Another portion of 4Q376 commands the people to do all that the priest tells them “in accordance with all this judgment,” which may be a reference to the decisions of God that were rendered through the Urim.
Another one of the Dead Sea Scrolls, 4QpIsad, mentions the Urim and the Thummim and describes how they give light “like the sun in all its radiance.” This text is unfortunately fragmentary, but appears to identify the twelve gemstones in the high priest’s breastplate with the Urim and/or Thummim. Van Dam (The Urim and Thummim, 232) argues that the ancient traditions which describe the supernatural illumination of the stones are compelling, and suggests that this interpretation of the Urim and the Thummim only fell out of favor in Western scholarship since the seventeenth century due to a rationalistic, anti-supernatural worldview.
The Talmud and other Jewish literature contain multiple traditions regarding the Urim and the Thummim (see this page or this one, and search within the page for “Urim”). According to one tradition, when an inquiry was made, various letters of the names of the twelve tribes which were engraved on the stones would protrude or light up in order to spell out an answer. But since the names of the twelve tribes do not contain all the letters of the alphabet, this theory was expanded by various rabbis to include additional stones with additional words, and to have the illuminated letters pop out from the stones and arrange themselves into words. However, it must be remembered that these traditions come from a period centuries after the Urim and the Thummim were no longer in use. On the whole, the theory of illuminated letters seems like an embellishment based on the known fact that the stones in the breastplate would illuminate when the high priest spoke a message from God in response to an inquiry.
A more believable Jewish tradition (from the same Talmud tractate) taught that the inquirer would face the priest and his breastplate, while the priest turned his head toward the ark of the covenant. The inquirer would ask a question in a soft tone of voice, and the priest would verbally state God’s answer to the question. This looks like the method by which the process happened in passages which describe people inquiring of God (Judg 1:1-2; 20:27-28; 1 Sam 10:22; 23:9-12; 30:7-8; 2 Sam 2:1; 1 Chr 14:10-15). It is interesting that the Talmud also affirms that the priest who led the army into battle was allowed to wear the Urim and the Thummim when he did so, even if he was not the high priest. This fits with Josephus’ claim that the stones of the breastplate would illuminate at the start of a battle in order to signify God’s presence with the people. The Talmud also claims, believably, that only leaders of the nation could inquire of God through the Urim; the Urim could not be used by ordinary people or for common, everyday matters.
The suggestion that the high priest would receive a prophetic oracle from God in response to a formal inquiry through the Urim is the only one that that fits with the biblical passages noted above. The Urim and the Thummim are best viewed as separate objects. The Thummim (“perfections”) are never mentioned independently of the Urim (“lights”), but the Urim are twice mentioned in the Bible independently of the Thummim (Num 27:21; 1 Sam 28:6), both times in the context of using the Urim to inquire of God. The Thummim are never said to be used to inquire of God; they are simply mentioned as part of the high priest’s breastplate. Following Josephus’ description, the Thummim (“the blameless ones”) were the two onyx stones on the shoulder pieces of the high priest’s vestments, inscribed with the names of the twelve tribes of Israel. They would light up brilliantly to signify that God had accepted the sacrifices offered on the Day of Atonement, thereby making the tribes of Israel blameless before Him. The Urim (“the ones shining like firelight”) were the twelve gemstones in the high priest’s breastplate, inscribed with the names of the twelve tribes of Israel. These stones would light up in brilliant colors to verify that the words spoken by the high priest in response to an inquiry were indeed received from God, as well as to signify that God had heard the people’s prayer for victory when they went out to battle. The shining of these stones showed visibly that God’s glory was manifested through the twelve tribes of Israel. The name of the tribe of Levi was not listed among “the blameless ones” (Thummim) or “the shining ones” (Urim), but is identified with the high priest as “the godly one” in Deuteronomy 33:8—And of Levi he said, “Your blameless ones and your shining ones are with your godly one.” In Old Testament times, the priests functioned as mediators between God and the people, representing both the people to God and God to the people. The Urim and the Thummim, with the names of the twelve tribes of Israel inscribed on them, were an important aspect of the mediatorial role of the priesthood.
The Mishnah states that the Urim and the Thummim ceased to exist “when the former prophets died” (search within this PDF for “Urim”), which the Talmud interprets as a reference to the time when the first temple was destroyed (search within this page for “Urim”). Josephus says the stones in the high priest’s breastplate stopped shining some two hundred years before he wrote (i.e., after the death of John Hyrcanus in 104 BC) due to the sins of the nation (Ant. 3.8.9 §218, available here; search within the page for “Now this breastplate”; compare J.W. 1.2.8 §§68-69, available here; search for within the page for “He it”). Ezra 2:63 and Nehemiah 7:65 indicate that the Urim and the Thummim did not exist when the Israelites initially returned from exile, though there was an expectation that the high priest might have them at a future time. John 11:49-52 records an instance of the high priest receiving prophetic revelation from God as late as a few weeks before Jesus was crucified, though it does not say whether this revelation involved the Urim and the Thummim. Practically speaking, the use of the Urim to inquire of God seems to have ceased when a line of prophets arose (partway through the reign of David), after which time persons desiring a message from God would direct their inquiries to a prophet instead of the high priest. However, it seems likely that the Urim and the Thummim continued to shine miraculously in certain circumstances even after they ceased to be used for inquiring of God. If Josephus is to be believed, they stopped shining about one hundred years before the birth of Jesus Christ.