Chapter 21

  1. The Birth of Isaac

    • God kept his promise to Abraham and Sarah. When Abraham was 100 years old Sarah gave birth to his son and Abraham named him Isaac. When Issac was 8 days old, Abraham circumcised him as God had commanded.

      • It had been 25 years since God originally made this promise to Abraham!

    • Sarah said, “God has made me laugh and everyone who hears about this will laugh with me. Who would have ever thought that I would have any children at all, but here in Abraham’s old age I have given him a son.”

2. Hagar and Ishmael Sent Away

    • Issac grew and Abraham held a big feast on the day Isaac was weaned.

      • “Some ancients say children were not weaned until 12 years of age and some say five years, but the most reliable research indicates an age of three. Isaac was young.” (Guzik)

    • During the feast, Sarah saw Ishmael (Abraham’s son by his slave Hagar) making fun of Isaac, and Sarah told Abraham to get rid of Hagar and her son. Sarah proclaimed that Ishmael would not be a shared heir of Abraham’s inheritance.

      • “This conflict between the two sons was almost inevitable, even though they were some 13 years apart.” (Guzik)

      • “In Galatians 4, the Jewish legalists who troubled the Galatians protested they were children of Abraham and thus blessed. Paul admitted they were children of Abraham, but they were like Ishmael, not Isaac! The legalists claimed Abraham as their father. Paul asked who was their mother, Hagar or Sarah? Ishmael was born of a slave, and born according to the flesh. Isaac was born of a freewoman, and born according to promise. Even so, the legalists promoted a relationship with God based in bondage and according to the flesh. The true gospel of grace offers liberty in Jesus Christ and is a promise received by faith.” (Guzik)

    • Sarah’s demand was very difficult for Abraham because he loved his son Ishmael. But God told Abraham, “Don’t worry about Ishmael and Hagar. Do whatever Sarah asks you to do because your lineage will be traced through Isaac. However, because Ishmael is your son, I will make a nation of Ishmael’s descendants too.”

      • Some of us may read these passages and erroneously applying today’s societal norms feel outraged that Sarah would demand that Abraham send away his very own child, and perplexed that God would side with Sarah and tell Abraham to send Ishmael away. This is where the cultural context of this story becomes especially valuable. Bible Blender’s article, The Birth of Isaac and Ishmael Sent Away, sheds some light on the appropriate cultural context, “The story of Hagar and Ishmael is indeed sad and required a tough decision in order to ensure God’s promise through Isaac could be fulfilled. Ancient law codes pass inheritance rights to the son that is “accepted” by the father and thus, Ishmael had to be sent away in order to pass the inheritance rights to Isaac. Still, God’s promise to take care of Ishmael brings the story to a happy end.”

-We must also keep in mind that Ishmael was 16 or 17 years old at the time of this event. The Bible Bender article linked above also notes, “There was a custom in place during this time which dictated that a man of 16 years old be sent into the wild, carrying a few days’ provisions, as a show of manhood. The sending away of Ishmael may have been a part of this common practice.”

    • So early the next morning Abraham gave Hagar bread and a bottle of water and sent her and Ishmael away.

    • Upon leaving, Hagar and Ishmael wandered in the wilderness of Beer-sheba. When they ran out of water, she left Ishmael under a bush, went a short distance away and cried saying “I can’t stand to watch my son die!”

    • God spoke to Hagar from heaven saying, “What’s wrong? Don’t be afraid because I have heard Ishmael’s cries. Go to him and take care of him because I’m going to make a great nation from his descendants.”

    • God then opened her eyes and revealed to her a well nearby. Hagar filled their water bottle and gave Ishmael a drink.

      • “As God protected and preserved them out in the desert; He answered them by hearing the voice of the lad. God showed special favor to Ishmael because he was a descendant of Abraham…The descendants of Ishmael became the Arabic people.” (Guzik)

    • God was with Ishmael as he grew up. He was an archer and made his home in the Wilderness of Paran. Hagar arranged his marriage to a woman from Egypt.

3. Abraham’s Covenant with Abimelech

    • At this time, Abimelech and the commander of his army said to Abraham, “God is obviously with you, helping you in all that you do. Swear to me by God that you will keep your agreements with me and my descendants. I have been loyal to you, so swear that you will also be loyal to me in this land that you live in as a foreigner.”

      • “This was probably not the same Abimelech of Genesis 20. Abimelech was the title of a ruler among the Canaanites, not a specific name.” (Guzik)

    • Abraham swore to this, but then he told Abimelech that his servants had siezed a water well that belonged to Abraham.

    • Abimelech said, “I had no idea. You haven’t said anything about it until today.”

    • Then Abraham gave Abimelech some sheep and cattle and they made a covenant between them.

    • Abraham had set aside 7 extra female lambs and Abimelech asked what they were for. Abraham responded that they were his payment to Abimelech to serve as witness to Abimelech’s agreement that Abraham had dug the well.

      • According to the NLT Illustrated Study Bible commentary, “Abraham’s gifts to Abimelech secured his legal right to dwell peaceably in the land and to claim ownership of the well.”

    • Because of the oath sworn there, this place was named Beer-sheba. Abimelech and his army commander returned to their home in the land of the Philistines.

Map from

– Beer-sheba means “well of the oath”.

      • The NLT Illustrated Study Bible also notes, “The Philistines in Genesis are different from the Philistines of Judges through Kings. The earlier Philistines had Semitic names (e.g. Abimelech) and Canaanite culture. The later Philistines were apparently of Greek origin, with Greek customs and culture. They seem to have arrived in Canaan by sea from the Aegean area around 1200 B.C., during the time of the judges. Probably the name of the later Philistines was used here to simply describe the region’s earlier inhabitants.”

    • Abraham planted a tamarisk tree there and worshiped the Lord.

    • Abraham lived here as a foreigner for a long time.

      • “A tamarisk tree requires a lot of water; this act indicated Abraham’s security in his land rights and his faith that God would provide water in this desert area.” (NLT Illustrated Study Bible commentary)