Qos (Edomite: 𐤒𐤅𐤎 Qāws, later Qôs; Hebrew: Qōs) also Qaus ( Qa-uš), or Koze (Greek: Kωζαι Kōzai) was the national god of the Edomites. He was the Idumean structural parallel to Yahweh. The name occurs only twice in the Old Testament (if a possible allusion in an otherwise corrupted text in the Book of Proverbs is excluded) in the Book of Ezra and Nehemiah as an element in a personal name, Barqos ("son of Qos", compare the Hebrew "Benaiah" meaning "son of Jah"), referring to the 'father' of a family or clan of perhaps Edomite/Idumaean nəṯīnīm or temple helpers returning from the Babylonian exile. Outside the Bible, Qos is frequently invoked in names found on documents recovered from excavations in Elephantine, where a mixed population of Arabs, Jews and Idumeans lived under the protection of a Persian-Mesopotamian garrison. Origins, meaning and cult The word "Qos" is never used on its own in the Tanakh, however it does unambiguously appear twice as an element in a personal name in Ezra 2:53 and Nehemiah 7:55 as Barqos, "son of Qos". The name Qōs itself may mean bow. Qōs became identified with Quzah, "the archer" in the north Arabian pantheon, worshiped both as a mountain and a weather god. The similarity of the name would have permitted an assimilation of Qōs to the Arabian god of the rainbow, qaws quzaḥ. The worship of Qōs appears to originally have been located in the Ḥismā area of southern Jordan and north-western Arabia, where a mountain, Jabal al-Qaus, still bears that name. He entered the Edomite pantheon as early as the 8th century M. Rose speculates that, prior to Qōs's advent, Edom may have worshipped Yahweh—early Egyptian records reference a place called yhw3w in the land of the Shasu—and the former then overlaid the latter and assumed supremacy there when the Idumeans lost their autonomy under Persian rule, perhaps compensating for the destruction of national independence, a mechanism similar to that of the strengthening of Yahweh worship after the fall of the Jewish kingdom. Qōs is described as a "King", is associated with light, and defined as "mighty". His works are described as ones where he "adorns, avenges, blesses, chooses(?) gives." Costobarus I, whose name meant "Qōs is mighty" was a native Idumean descended from a priestly family attached to this cult. After Herod had placed him in command over (στρατηγὀς) Idumea, Costobarus, supported by Cleopatra,