“Abraham became the father of Isaac. The sons of Isaac were Esau and Israel.”
Once again, chapter 25 of Genesis is the main source of information. Esau and Israel are twin boys born to Isaac and his wife Rebekah when he was 60 years old, after 20 years of marriage. The rest of the relationships between the 2 twin brothers can be found in Genesis, chapters 25-33. Esau was technically the first born, but Israel or Jacob as he was called in Genesis tricks him into giving up his birth right. Throughout Chronicles, Esau’s brother is continually called Israel, while the opposite was true in the Book of Genesis, where he was called Jacob.