Question: One of the “contradictions” in scripture that some people point out is the number of Abraham’s sons. Galatians:4:22 says he has two, but other verses in Genesis say he has more (or just one). I know that one explanation for Abraham’s being said to “have two sons” is because Paul used it to model the covenants of law and grace. I generally agree with the explanation, but the tricky part is that in today’s world when we say we “have two kids,” and we really have three, others may consider that lying. That makes this explanation somewhat difficult. How do we approach this “contradiction”?
Response: There is no contradiction. We need to examine all the scriptures pertaining to this. The Lord had promised Abraham that from his “seed” (singular) would come forth many descendants. With the delay of the fulfillment of this promise, Sarah and Abraham devised another plan when Sarah urged Abraham to have relations with her handmaid, Hagar. As a result, “Hagar bare Abram a son: and Abram called his son’s name, which Hagar bare, Ishmael” (Genesis:16:15).
But the Lord rejected their plan, and when Abraham asked God to accept Ishmael as the child of promise, in Genesis:17:18 we read that “Abraham said unto God, O that Ishmael might live before thee!” But God repeated His promise: “And God said, Sarah thy wife [emphasis added] shall bear thee a son indeed; and thou shalt call his name Isaac: and I will establish my covenant with him for an everlasting covenant, and with his seed after him” (Genesis:17:19).
The Lord viewed Isaac as “the son,” that is, the “promised son,” regardless of Sarah and Abraham’s plan. When the Lord told Abraham to take Isaac and offer him for a sacrifice, He said, “Take now your son, your only son Isaac, whom you love, and get you into the land of Moriah; and offer him there for a burnt offering upon one of the mountains which I will tell you of” (Genesis:22:2).
By common usage, Isaac wasn’t the only son, because Ishmael was the eldest son. But the passage in Genesis:22:2 (“your only son Isaac”) used a particular phrase. The Hebrew word used for “only” is yachiyd, which means “unique” or “only begotten” (that is, “special”).
Furthermore, Ishmael had already been rejected and cast out. In Genesis:21:10, Sarah “...said unto Abraham, Cast out this bondwoman and her son: for the son of this bondwoman shall not be heir with my son, even with Isaac.” The promise applied only to Isaac. He was the heir and the one specifically named by God.
Afterwards, there were other biological sons. Genesis:25:2 tells us that after the death of Sarah, Abraham took another wife named Keturah. “And she bore him Zimran, and Jokshan, and Medan, and Midian, and Ishbak, and Shuah.” Nevertheless, Isaac remains the only son of the promise, for in Genesis:25:6 we are told, “…unto the sons of the concubines, which Abraham had, Abraham gave gifts, and sent them away from Isaac his son, while he yet lived, eastward, unto the east country.”