Discussion Guide: Genesis 21 & Galatians 4:21-31


  • What difference does it make who your parents are? Are there advantages or challenges that are created as a result of who your parents are?

When did it happen?

Abraham’s age when God first gave the promise 75 years old
Abraham’s age when Ishmael is born 86 years old
Abraham’s age when Isaac is born 100 years old
Sarah’s age when Isaac is born 90 years old
Ismael’s age when he is sent away 15-17 years old


The Impossible Becomes Reality – Genesis 21:1-7

  • How long had Abraham been waiting for God to fulfill His promise? (Hint: compare Genesis 21:5 with 12:4)
  • Abraham obeys God’s instruction from Genesis 17:19 by naming his son Isaac, which means “he laughs.” Why was this an appropriate name for the child?
  • How has Sarah’s attitude changed in response to having the promised child?
  • How is the birth of Isaac similar to the birth of Jesus?

It’s No Laughing Matter – Genesis 21:8-21

  • Why did Sarah want Abraham to send Hagar and Ishmael away?
  • How were Abraham’s past sins catching up to him? What reasons might Abraham have had for not wanting to see Hagar and Ishmael go? Why was it necessary?
  • What was different about Abraham’s relationship with Sarah/Isaac and Hagar/Ishmael that Hagar/Ishmael?
  • How did God provide for Hagar and Ishmael? Why?

It Makes a Difference Who Your Mom Is –Galatians 4:21-31

  • How does Hagar/Ishmael parallel those seeking to live by the old covenant law (the Jews of Paul’s day)? How does Sarah/Isaac parallel those living by the new covenant of grace in Jesus Christ?
  • What does it mean to be a child of promise (4:28)? Read Galatians 3:7 and 29. How do we become heirs of God’s promises to Abraham?
  • For extra consideration: Read Romans 9:6-13. Note: Being a physical descendant of Abraham (a Jew) doesn’t make one a child of God. Instead, it is by God’s grace, not works (seen with both Isaac/Ishmael and Jacob/Esau) that we receive the promises.


Making Peace –Genesis 21:22-34

  • How is this encounter with Abimelech different than Abraham’s first encounter with him? How is God beginning to fulfill his promise to Abraham to be a blessing to the nations in his interactions with Abimelech?
  • What was the significance and value of this well in Abraham’s life?
  • The name of God given in verse 33 is “God Everlasting” (El Olan). How has the everlasting nature of God been important in Abraham’s life up to this point? How is God’s everlasting nature seen related to us through this study?



  • Are there things we are tempted to trust in other than God’s promises? What are they? How does God’s fulfillment of his promise to Abraham give us confidence to trust him today?
  • Are there some things that we are attached to that God is calling us to let go?
  • Do you live like you are God’s son or God’s employee? Does his grace give you a desire to honor him, or are you seeking to appease him by your works?
  • How are you, as one who has inherited the promises of Abraham, being a blessing to the nations?
  • Through our study tonight did you notice how Scripture is telling one coherent story?