Key Verses: Genesis 21:1-2, 21:6, 21:12-13
The LORD visits Sarah as He promised. Sarah conceives and bears Abraham a son in his old age at the appointed time. Abraham names him Isaac, circumcising him on the eighth day according to God’s command. Abraham is 100 years old. Sarah says, “God has made laughter for me; everyone who hears will laugh over me.” She marvels: “Who would have said to Abraham that Sarah would nurse children?” At Isaac’s weaning feast, Sarah sees Ishmael (Hagar’s son) laughing/mocking. She tells Abraham to cast out the slave woman and her son-Ishmael shall not be heir with Isaac. This distresses Abraham because of his son. God tells Abraham to listen to Sarah: through Isaac shall his offspring be named. But God will also make a nation of Ishmael because he’s Abraham’s offspring. Abraham rises early, gives Hagar bread and water, and sends her away with the child. She wanders in the wilderness of Beersheba. Water runs out; she places the child under a bush and sits at a distance, unable to watch him die. The child cries. The angel of God calls from heaven, asking Hagar why she weeps. “God has heard the boy’s voice.” He promises to make Ishmael a great nation. God opens her eyes to see a well. She gives the boy water. God is with Ishmael; he grows up in the wilderness, becoming an archer, dwelling in Paran. Hagar gets him an Egyptian wife.
God’s faithfulness is emphasized-He “visited” and “did” as He promised. Isaac’s birth fulfills decades of promises. His name (“laughter”) memorializes Sarah’s initial unbelief transformed to joyous amazement. The conflict between Isaac and Ishmael represents flesh versus promise (Galatians 4:29-child of flesh persecutes child of promise). Sarah’s harsh demand is God’s will (21:12)-God’s promises center on Isaac, not Ishmael. Yet God graciously cares for Hagar and Ishmael, promising to make him a nation. The wilderness crisis parallels Genesis 16-God hears, sees, provides. “God heard” (same root as Ishmael’s name) the boy’s cry. This demonstrates God’s compassion extends beyond the covenant line. Paul uses this narrative allegorically in Galatians 4:21-31-Hagar represents Sinai covenant (slavery), Sarah represents Jerusalem above (freedom). Isaac’s birth by promise prefigures believers’ spiritual birth.
Key Terms & Words:
- פָּקַד (paqad) - Genesis 21:1 - “Visited”; God’s faithful attention and action to fulfill promises
- צָחַק (tzachaq) - Genesis 21:6, 9 - “Laugh”; Isaac’s name, also describing Ishmael’s mocking
- זֶרַע (zera) - Genesis 21:12 - “Offspring”; through Isaac, not Ishmael, the line continues
Cross-References:
- Romans 9:7-9 - Not all Abraham’s children are children of promise; in Isaac shall offspring be named
- Galatians 4:21-31 - Allegory of two covenants: Hagar and Ishmael (flesh), Sarah and Isaac (promise)
- Galatians 4:29 - Child of flesh persecuted child of Spirit, so it is now
- Hebrews 11:11 - By faith Sarah received power to conceive
- Luke 1:37 - Nothing will be impossible with God
Discussion Questions:
- How does Isaac’s miraculous birth demonstrate God’s faithfulness to fulfill promises in His timing, and what does this teach us about waiting on God?
- Why does God command Abraham to listen to Sarah and send Ishmael away (21:12), and what does this teach about God’s sovereign choice in election?
- How does Paul’s allegory in Galatians 4 help us understand the spiritual significance of Isaac and Ishmael representing children of promise versus children of flesh?