I was asked the following question:
Was Job an Israelite or Gentile?
It is hard to say for certain, because we are not told in the book. Peleg, Noah’s great-great-great-great grandson through Shem, had a brother named Joktan who had a son named Jobab, as we read in Genesis 10:29. If this Jobab was the same as Job, that would make Job Abraham’s great-great-great-great uncle’s son.
29. Ophir, Havilah, and Jobab. All these were the sons of Joktan.
Edom, the nation descended from Esau, once had a king named Jobab. He is actually listed as the second king of Edom. If this was Job (Job was certainly rich and important enough to have been a king,) then he was related to Israel, but not actually an Israelite, but a descendent of Abraham and Isaac and Esau. You can read about him in Genesis 36:33.
33. And when Bela died, Jobab the son of Zerah of Bozrah reigned in his place.
This Jobab is actually the one that the Septuagint identifies as Job in a section added at the end of the book.
Issachar, one of the fathers of the twelve tribes, had a son named Job. This would make him the grandson of Israel. If so, he lived before the Israelites were made slaves in Egypt, and was an Israelite. Genesis 46:13 talks about this.
13. The sons of Issachar were Tola, Puvah, Job, and Shimron.
There were also two Benjamites named Jobab, but they were late enough that it seems unlikely that Job was either of them.
One hint may be the identity of Job’s friends. There is an Eliphaz who is the son of Esau in Genesis 36:4, 10-12, 15-16; I Chronicles 1:35-36. If this was the Eliphaz of the story, it would be too late for the first Job. Though if Job was an Edomite, it would make sense that he would be friends with another descendant of Esau, yet perhaps (?) Eliphaz would have lived too early to have been friends with the Job who was also descended from Esau. If so, this would make Issachar’s son the most likely candidate. The other two friends are not mentioned anywhere else, so they do not help us.
So it is hard to say for sure who Job was. Take your pick. The Septuagint thinks he was the one descended from Esau. But if the Eliphaz who was Esau’s son is the same Eliphaz, the one who was descended from Issachar may be more likely. So in the final analysis it is hard to say. He may or may not have been an Israelite.