Qos also Qaus, or Koze was the national god of the Edomites. He was the Idumean structural parallel to Yahweh. The name occurs only twice in the Old Testament in the Book of Ezra and Nehemiah as an element in a personal name, Barqos, 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.

Edom was an ancient kingdom in Transjordan, located between Moab to the northeast, the Arabah to the west, and the Arabian Desert to the south and east. Most of its former territory is now divided between present-day southern Jordan and Israel. Edom appears in written sources relating to the late Bronze Age and to the Iron Age in the Levant.