Only Son

Question

Ishmael had already been born, so Abraham had more than one son (Gen. 16). If Abraham had more than one son, why is Isaac called his only son? (Gen. 22:2).

Answer

Genesis 22:2 Then God said, "Take your son, your only son, Isaac, whom you love and go to the region of Moriah. Sacrifice him there as a burnt offering on one of the mountains I will show you."

Indeed, Abraham had many sons as we're told in Genesis 25, but these sons were born later. The recently banished Ishmael in Genesis 21:14-16 was also Abraham's son, but he was conceived by a concubine and therefore not heir to the promised inheritance (Gal. 4:21-31). God had told Abraham, "It is through Isaac that your offspring will be reckoned." (Gen. 21:12; cf. Heb. 11:18). So, Isaac was a special or "beloved" son. Isaac's death would have meant the end of the line of promise (Jer. 6:26; Amos 8:10; Zec.12:10). God also has many sons (John 1:12; Rom. 8:14; Phil. 2:15; 1 John 3:1; 3:2), but one "beloved son" (Matt. 3:17; Mark 1:11; Luke 3:22; John 1:18; 3:16; 2 Pet. 1:17).

The language used here was to show that Isaac was a special son, the son of a free-woman and not the son of a bond-woman, the son of promise that was later to be understood as a shadow or type of Christ.

Answer by Dr. Joseph R. Nally, Jr.

Dr. Joseph R. Nally, Jr., D.D., M.Div. is the Theological Editor at Third Millennium Ministries (Thirdmill).