Genesis 20-21

Someone has said that God is seldom early. He is never late. He is always right on time. By human standards, God was late with the birth of a son to Abraham and Sarah. After all, they were both well past the child-bearing age. But God does not always set his clock to correspond to our digital watches. In today’s passage, proving that nothing is impossible with God, the son of promise was born.

Our focus today will be on Genesis 21:1-21. But before we get there, let me summarize Abraham’s interaction with King Abimelech in Genesis 20 and 21:22-34.

Back in Genesis 12, Abraham told the Egyptians that Sarah was his sister because he was afraid if they found out she was his wife, they might kill him and take her. Well, Abraham is at it again. He told Abimelech, king of Gerar[1], the same half-truth for the same reasons. God communicated the truth about Sarah to Abimelech in a dream, and the shaken ruler summoned Abraham and asked, “What have you done to us?” (Genesis 20:9) Later, when Abimelech’s servants and Abraham argued over the use of a water well, Abimelech requested a treaty[2] because the king realized two things: God was with Abraham, and Abraham could act deceptively. Abraham named the well he secured “Beersheba,” meaning “well of the oath” or “well of the seven” because he gave Abimelech seven lambs as part of the agreement. One more thing. After they swore an oath to each other, Abraham planted a tamarisk tree in the area to remind himself that God would provide water. At Beersheba, Abraham “called on the name of the Lord, the Eternal God” (Genesis 21:33 NIV).

But Abraham has more exciting events going on in his life than making treaties. Remember, in Genesis 18, God said that he would return in a year and Sarah would have a son.

Genesis 21:1-2
The Lord visited Sarah as he had said, and the Lord did to Sarah as he had promised. And Sarah conceived and bore Abraham a son in his old age at the time of which God had spoken to him.

God always keeps his promise. He allowed Sarah to conceived by her union with Abraham just as he promised. They named him Isaac, which means “he laughs.” Interestingly, a year earlier, both Abraham and Sarah had laughed in disbelief when God told them they were going to have a son at such an old age. Now, they were laughing with joy.

Genesis 21:6-7
And Sarah said, “God has made laughter for me; everyone who hears will laugh over me.” And she said, “Who would have said to Abraham that Sarah would nurse children? Yet I have borne him a son in his old age.”

When the newborn was eight days old, Abraham circumcised Isaac “as God had commanded him” (Genesis 21:4). The son of the covenant was now marked with the sign of the covenant.

There was much laughter in the home until there wasn’t. Most scholars believe that, at this point in history, children were nursed for three years. When Isaac was weaned, Abraham celebrated the milestone with a great feast. But during this special occasion, Sarah saw Ishmael, who now would be sixteen or seventeen, mocking Isaac. Exactly what he was doing, we don’t know, but for Sarah, that was the last straw. She perceived Ishmael as a threat and told Abraham, “Cast out this slave woman with her son, for the son of this slave woman shall not be heir with my son Isaac” (Genesis 21:10). Can you imagine how difficult that request was for Abraham, who loved Ishmael?

Genesis 21:11-13
And the thing was very displeasing to Abraham on account of his son. But God said to Abraham, “Be not displeased because of the boy and because of your slave woman. Whatever Sarah says to you, do as she tells you, for through Isaac shall your offspring be named. And I will make a nation of the son of the slave woman also, because he is your offspring.” 

Early the next morning, Abraham gave Hagar food and water and sent her and Ishmael on their way. Scripture records that Hagar “departed and wandered in the wilderness of Beersheba” (Genesis 21:14). When the water was gone, Hagar put her weakened son under a bush so he could die. She went a distance away so she did not have to watch him suffer. Hagar “lifted up her voice and wept” (Genesis 21:16). Then God came.

Genesis 21:17-21
And God heard the voice of the boy, and the angel of God called to Hagar from heaven and said to her, “What troubles you, Hagar? Fear not, for God has heard the voice of the boy where he is. Up! Lift up the boy, and hold him fast with your hand, for I will make him into a great nation.” Then God opened her eyes, and she saw a well of water. And she went and filled the skin with water and gave the boy a drink. And God was with the boy, and he grew up. He lived in the wilderness and became an expert with the bow. He lived in the wilderness of Paran, and his mother took a wife for him from the land of Egypt.

God keeps his promises. He promised to give Abraham and Sarah a son. He did. God promised Hagar that her son would become a great nation. He did. And…God will always deliver on his promises to you and me as well. And the greatest promise is Jesus. When we trust in him, we will live forever.

I just got off the phone with a pastor who is meeting with a family going through a challenging time. In the next few days, their son will die. We know the Eternal God promises that because of our great Savior, who came through the descendants of Abraham and Isaac, their son will live forever in heaven. This is the ultimate promise that will always be fulfilled in the life of a believer!

PERSONAL TIME WITH GOD
Read Genesis 20-21. Reflect on the truth we are reminded of in this passage—that God always keeps his promises. Rejoice in the fact that the greatest promise is heaven—forever with the Lord.

Prayer and Application
Thank God for the promise of heaven—all because of Jesus. If God has that covered for you, he can handle all the other challenges along the way.

Have Questions?
Send us any questions you have. Our team is here to assist you as you explore God’s Word. Simply submit your question below, and we’ll get back to you soon.

[1] Gerar was located around seventy miles southwest of present-day Jerusalem.
[2] Literally “cut a covenant.” They halved animals and walked between the pieces.