Genesis 21: God Keeps His Promise and Isaac is Born

Both Abraham and Sarah laughed when the Lord told them that in a year’s time, Sarah would become pregnant and bear Abraham a son. What was so hard to believe was that Sarah was 90 and Abe was 100 years old. But, God kept His promise! Let’s dig in….

Genesis 21:1-20 – the Birth of Isaac

The Lord kept his word and did for Sarah exactly what he had promised. She became pregnant, and she gave birth to a son for Abraham in his old age. This happened at just the time God had said it would. And Abraham named their son Isaac. Eight days after Isaac was born, Abraham circumcised him as God had commanded. Abraham was 100 years old when Isaac was born.

And Sarah declared, “God has brought me laughter. All who hear about this will laugh with me. Who would have said to Abraham that Sarah would nurse a baby? Yet I have given Abraham a son in his old age!”

Genesis 21:1-7 NLT

Nothing is Impossible with God!

There are many more impossible promises that God made AND kept…

“The Son of Man is going to be betrayed into the hands of his enemies. He will be killed, but three days later he will rise from the dead.”

Mark 9:31 NLT


Hagar and Ishmael Depart

So the child grew and was weaned. And Abraham made a great feast on the same day that Isaac was weaned.

And Sarah saw the son of Hagar the Egyptian, whom she had borne to Abraham, scoffing. 10 Therefore she said to Abraham, “Cast out this bondwoman and her son; for the son of this bondwoman shall not be heir with my son, namely with Isaac.” 11 And the matter was very displeasing in Abraham’s sight because of his son.

12 But God said to Abraham, “Do not let it be displeasing in your sight because of the lad or because of your bondwoman. Whatever Sarah has said to you, listen to her voice; for in Isaac your seed shall be called. 13 Yet I will also make a nation of the son of the bondwoman, because he is your seed.”

14 So Abraham rose early in the morning, and took bread and a skin of water; and putting it on her shoulder, he gave it and the boy to Hagar, and sent her away. Then she departed and wandered in the Wilderness of Beersheba. 15 And the water in the skin was used up, and she placed the boy under one of the shrubs. 16 Then she went and sat down across from him at a distance of about a bowshot; for she said to herself, “Let me not see the death of the boy.” So she sat opposite him, and lifted her voice and wept.

17 And God heard the voice of the lad. Then the angel of God called to Hagar out of heaven, and said to her, “What ails you, Hagar? Fear not, for God has heard the voice of the lad where he is. 18 Arise, lift up the lad and hold him with your hand, for I will make him a great nation.”

19 Then God opened her eyes, and she saw a well of water. And she went and filled the skin with water, and gave the lad a drink. 20 So God was with the lad; and he grew and dwelt in the wilderness, and became an archer. 21 He dwelt in the Wilderness of Paran; and his mother took a wife for him from the land of Egypt.

Genesis 21:8-21 NKJV

Points to Ponder

  • Ishmael was around 16-17 years old. Some Bible versions make it sound like he was a little boy. This is why I switched to the New King James Version, which calls him a “lad”. That makes more sense.
  • Even when Hagar thought she was alone dying with Ishmael in the wilderness, God was with them all the time.
  • In Genesis 16, God did tell Hagar that Ishmael would have “open hostility against his relatives.” That which started in this chapter, still goes on today with the hostilities between Arabs and Jews in the Middle East.
  • As Christian believers, we need to keep the nation of Israel in our prayers. I pray that God’s plan of Shalom — peace, wholeness and completion — will come to fruition with both Jew and Arab knowing Jesus Christ as their Messiah.

The Beginning of a Royal Lineage

Many times in the both the Old and New Testaments someone will call on the God of Abraham, Isaac and Jacob. Isaac’s son, Jacob, and God will change His name, like He changed His grandfather’s name, to Israel. Jacob’s sons will become the 12 Tribes of Israel. See, all this was part of God’s plan. Check out this short video on the Tribes of Israel…

12 Tribes of Israel

And, in case you missed them, both Luke and Matthew show Jesus’ royal lineage…

The Importance of the Old Testament

One false teaching that is floating around the world is Replacement Theology. What I’m trying to accomplish is to show that without the Old Testament, we wouldn’t have the story of Jesus. It will become even more obvious as we continue. History is important. If we don’t learn from history, we are doomed to repeat it.

Faith Lessons

  1. If God makes promises, He keeps them.
  2. God sees everything. Even when you don’t feel Him close, He is there.
  3. You can trust God.
  4. God provides. As He provided Sarah and Abraham with an heir, and Hagar with water and hope, He will provide all you need if you sincerely seek Him.
  5. God warns us to obey over and over again. Furthermore, we will see the consequences of disobedience as we go on.

Where Do You Stand?

Do you stand with God or with the world? If you’re not following Jesus, you’re following the world. Following the world is the wide road that leads to hell. Jesus is the ONLY WAY to salvation!

If you’re not sure if you’re saved or not, if you truly want to be born again and have the assurance of salvation, receive the Holy Spirit, feel His Shalom — a peace that surpasses all understanding, and get a 1-way, non-stop ticket to Heaven after you die, or that you won’t be left behind at the Rapture, which can happen at any moment, this is what you have to do…

Believe. Repent. Be Baptized. Receive the Holy Spirit.

  • Believe — have Faith — that Jesus is the Christ and He died taking your sins away forever and that He rose from the dead 3 days later.
  • Repent of your sins — stop sinning! Do a complete 180-degree turn in your life and surrender your life to Him. When you ask Jesus to forgive you He will. ALL your sins will be wiped clean — past, present, and future! And All means ALL!
  • Be Baptized by water baptism — show the world and yourself that you have died to your old life and are born again in Christ.
  • Receive the gift of Holy Spirit in your heart.

Invite Jesus into Your Heart and Receive the Gift of Grace, Joy, Peace, and the Confident Hope of Eternal Life…

His Eye is On the Sparrow

Soli Deo Gloria! To God Alone Be the Glory!

Top graphic by Yo Ministry from, (CC BY-NC-ND 4.0)

2 thoughts on “Genesis 21: God Keeps His Promise and Isaac is Born”

  1. Pingback: Genesis 22: The Ultimate Test of Man’s Faith from God – Seek the Truth

  2. Pingback: Esther 9-10: God Fulfills Promises Through Everyday Life and Humble People – Seek the Truth

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