Ishmael was a son of Abraham, born of Sarah’s maidservant Hagar in an attempt to bring into the world the son God had promised to Abraham and Sarah. Later, Isaac was born to Abraham and Sarah, and Hagar and Ishmael were driven away because of Ishmael’s attitude toward Isaac (Genesis 21:9–10, 14). But God still had plans for Ishmael. God promised Hagar that Ishmael, as a son of Abraham, would become a great nation (Genesis 21:17–18). The fulfillment is recorded in Genesis 25:12–18—Ishmael had twelve sons who became great rulers and eventually a nation of people. That came about in this way: Hagar, who was Egyptian herself, found a wife from Egypt for her son, and Ishmael settled in the desert of Paran (Genesis 21:21). Ishmael’s descendants “settled in the area from Havilah to Shur, near the border of Egypt as you go toward Ashur” (Genesis 25:18).
“And these are the names of the sons of Ishmael, by their names, according to their generations: the firstborn of Ishmael, Nebajoth; and Kedar, and Adbeel, and Mibsam, And Mishma, and Dumah, and Massa, Hadar, and Tema, Jetur, Naphish, and Kedemah” Genesis 25:13-15 The area of Havilah where Ishmael’s descendants lived is in the northern part of the Arabian Peninsula; Shur is a wilderness area between Beersheba in the Negev Desert and Egypt. Isaiah 60:7 mentions the descendants of Nebaioth and Kedar as those who raise flocks. The descendants of Ishmael became known as Arabs, which basically means “nomads.” From the beginning, the descendants of Ishmael were a warlike people, as “they lived in hostility toward all the tribes related to them” (Genesis 25:18). This fulfilled God’s earlier word about Ishmael “And he will be a wild man; his hand will be against every man, and every man's hand against him; and he shall dwell in the presence of all his brethren.” Genesis 16:12
Later, others settled in the Arabian Peninsula as well, including the descendants of Keturah’s sons (1 Chronicles 1:32–33) and some of Esau’s descendants, among them the Amalekites (Genesis 36:12). There is a popular theory common among Muslims and some Christians that Arabian Muslims are direct descendants of Ishmael. In fact, Muhammad was a major proponent of this idea, claiming to be a descendant of Ishmael according to the Quran. There is most likely some truth in this theory. Old records link the north Arabians with Ishmael’s descendants” (“Ishmael and the Bible,” Emmaus Journal 13:2, 2004). But it’s unlikely that all of those in Arabia are descendants of Ishmael, as the descendants of Keturah and Esau also lived in the Arabian Peninsula.
Although some modern Arabians could trace their lineage back to Ishmael, not all Arabians are descendants of Ishmael as Muslims claim. We know from the Bible that God made Ishmael into a great nation. His descendants can share in the blessings of Abraham by putting their faith in Jesus the Christ for salvation.