Ishbak

Ishbak (meaning leaving or who is empty) was one of the sons of Abraham by his concubine Keturah, listed in Genesis 25:2 and 1 Chronicles 1:32. He was a brother of Zimran, Jokshan, Medan, Midian, and Shuah — the six sons born to Abraham after Sarah's death who became ancestors of the peoples of northern Arabia and the surrounding regions. Abraham gave gifts to these sons and sent them away from Isaac eastward, to the east country (Genesis 25:6), separating them from the line of the covenant promise that passed exclusively through Isaac.

Ishbak's descendants are not separately traced in Scripture, and no tribe or people group is definitively identified with his name. He represents one of the many lines of descent from Abraham that populated the ancient Near Eastern world beyond the covenant community, illustrating that the scope of Abraham's fatherhood extended beyond Israel even as the covenant promise was narrowed to the Isaacline.