BIBLE CHAPTER STUDY
Genesis 21 — Birth of Isaac and Hagar's Dismissal
Genesis 21 fulfills God's promise to Abraham and Sarah by giving them a son in their old age, then resolves the tension between Isaac and Ishmael through Sarah's demand and God's command, and ends with a covenant at Beer-sheba.
Scripture
1And Jehovah visited Sarah as he had said, and Jehovah did unto Sarah as he had spoken.
2And Sarah conceived, and bare Abraham a son in his old age, at the set time of which God had spoken to him.
3And Abraham called the name of his son that was born unto him, whom Sarah bare to him, Isaac.
4And Abraham circumcised his son Isaac when he was eight days old, as God had commanded him.
5And Abraham was a hundred years old, when his son Isaac was born unto him.
6And Sarah said, God hath made me to laugh; every one that heareth will laugh with me.
7And she said, Who would have said unto Abraham, that Sarah should give children suck? for I have borne him a son in his old age.
8And the child grew, and was weaned: and Abraham made a great feast on the day that Isaac was weaned.
9And Sarah saw the son of Hagar the Egyptian, whom she had borne unto Abraham, mocking.
10Wherefore she said unto Abraham, Cast out this handmaid and her son: for the son of this handmaid shall not be heir with my son, even with Isaac.
11And the thing was very grievous in Abraham's sight on account of his son.
12And God said unto Abraham, Let it not be grievous in thy sight because of the lad, and because of thy handmaid; in all that Sarah saith unto thee, hearken unto her voice; for in Isaac shall thy seed be called.
13And also of the son of the handmaid will I make a nation, because he is thy seed.
14And Abraham rose up early in the morning, and took bread and a bottle of water, and gave it unto Hagar, putting it on her shoulder, and gave her the child, and sent her away: and she departed, and wandered in the wilderness of Beer-sheba.
15And the water in the bottle was spent, and she cast the child under one of the shrubs.
16And she went, and sat her down over against him a good way off, as it were a bowshot: for she said, Let me not look upon the death of the child. And she sat over against him, and lifted up her voice, and wept.
17And God heard the voice of the lad; and the angel of God called to Hagar out of heaven, and said unto her, What aileth thee, Hagar? fear not; for God hath heard the voice of the lad where he is.
18Arise, lift up the lad, and hold him in thy hand; for I will make him a great nation.
19And God opened her eyes, and she saw a well of water; and she went, and filled the bottle with water, and gave the lad drink.
20And God was with the lad, and he grew; and he dwelt in the wilderness, and became, as he grew up, an archer.
21And he dwelt in the wilderness of Paran: and his mother took him a wife out of the land of Egypt.
22And it came to pass at that time, that Abimelech and Phicol the captain of his host spake unto Abraham, saying, God is with thee in all that thou doest:
23now therefore swear unto me here by God that thou wilt not deal falsely with me, nor with my son, nor with my son's son: but according to the kindness that I have done unto thee, thou shalt do unto me, and to the land wherein thou hast sojourned.
24And Abraham said, I will swear.
25And Abraham reproved Abimelech because of the well of water, which Abimelech's servants had violently taken away.
26And Abimelech said, I know not who hath done this thing: neither didst thou tell me, neither yet heard I of it, but to-day.
27And Abraham took sheep and oxen, and gave them unto Abimelech; and they two made a covenant.
28And Abraham set seven ewe lambs of the flock by themselves.
29And Abimelech said unto Abraham, What mean these seven ewe lambs which thou hast set by themselves?
30And he said, These seven ewe lambs shalt thou take of my hand, that it may be a witness unto me, that I have digged this well.
31Wherefore he called that place Beer-sheba; because there they sware both of them.
32So they made a covenant at Beer-sheba: and Abimelech rose up, and Phicol the captain of his host, and they returned into the land of the Philistines.
33And Abraham planted a tamarisk tree in Beer-sheba, and called there on the name of Jehovah, the Everlasting God.
34And Abraham sojourned in the land of the Philistines many days.
What this passage means
The chapter opens by emphasizing divine faithfulness. The repetition that Jehovah 'visited Sarah as he had said' and 'did unto Sarah as he had spoken' frames the entire narrative: the long-deferred promise of an heir is now literally brought to pass. The named son, Isaac, whose name itself means 'laughter,' is given to Abraham at one hundred years old and to Sarah long past the natural age of childbearing, so that the chapter's central claim is that the child is the work of God's word, not of human capability.
Sarah's response (vv. 6–7) turns astonishment into doxology: 'God hath made me to laugh.' The laughter that once marked unbelief (Genesis 18:12) now becomes the laughter of joy and witness. Sarah's confession that she has borne a son in Abraham's old age is less a private reflection than a public testimony meant for 'every one that heareth,' so that the laughter becomes a shared acknowledgment of God's power to keep his word.
The second half of the chapter narrates the expulsion of Hagar and Ishmael and the covenant at Beer-sheba. Sarah demands that the bondwoman's son not inherit with her son Isaac, and God himself instructs Abraham to 'hearken unto her voice,' explaining that 'in Isaac shall thy seed be called.' Yet God also promises to make a nation of Ishmael because he is Abraham's seed. The chapter closes with Abraham acknowledged by Abimelech as one 'with whom God is,' a treaty of seven ewe lambs at the well, the place named Beer-sheba, and Abraham planting a tree and calling on 'the Everlasting God.'
Context
The provided material for Genesis 21 contains 34 verses with no surrounding chapter text supplied; the curated note simply identifies the chapter as backfilled material. The chapter is internally coherent and does not require external background to follow: it links the birth of Isaac to the prior promises of an heir, moves from that fulfillment to a household conflict over inheritance rights, and then to a covenant with a foreign king that secures Abraham's place in the land. The cross references supplied tie the chapter to Genesis 17 and 18 (where the promise of Isaac was given) and to passages that later reflect on promise versus flesh (Galatians 4:23, 28) and on the unfailing nature of God's word (Psalms 12:6, Matthew 24:35, Titus 1:2).
Key words in the original
- H6485 Hebrew pāqaḏ (H6485), glossed 'visited,' covers both friendly and hostile intent and includes the sense of overseeing, mustering, or caring for. In Genesis 21:1 it is used in its benevolent sense, signaling God's attentive intervention to fulfill his word to Sarah.
- H1696 Hebrew dāḇar (H1696), used twice in verse 2 as 'spoken' and earlier as 'promised' in verse 1, captures the idea of arranging or setting words. The chapter thus presents Isaac's birth not as a biological event but as the arranged outcome of God's spoken word.
- H4150 Hebrew môʿēḏ (H4150), translated 'appointed time' in verse 2, denotes a fixed time or season, often a festival or assembly. Its appearance here emphasizes that Isaac's birth occurs at the very moment God had set, underlining the precision of the divine promise.
Related verses
- Genesis 18:10 Genesis 18:10 is the prior announcement of the same promise: Sarah will bear a son. Placing it alongside Genesis 21 shows that the chapter's opening 'Jehovah visited Sarah as he had said' is the literal arrival of what was foretold at Mamre.
- Galatians 4:23 Galatians 4:23 contrasts Ishmael, born 'after the flesh,' with Isaac, born 'through promise.' This frames the dismissal scene in Genesis 21:9–14 as more than a family dispute: it distinguishes the covenant heir from the one born by human arrangement.
- Titus 1:2 Titus 1:2 speaks of 'eternal life, which God, who cannot lie, promised before times eternal.' Read with Genesis 21, it clarifies why the chapter can rest its weight on the repeated 'as he had said' and 'as he had spoken': the God who cannot lie is the one who 'visited' Sarah.
Common questions
Why is Sarah's laughter in verse 6 important if she laughed in doubt earlier?
In Genesis 18:12 Sarah laughed within herself from unbelief at the thought of bearing a son in old age. In Genesis 21:6 the same verb is repurposed: the laughter is now public and joyful, attributed to God's action. The chapter thus transforms doubt into testimony, and Sarah's confession in verse 7 that she has borne Abraham a son in his old age invites every hearer to share in acknowledging God's faithfulness.
Why does God tell Abraham to listen to Sarah's demand to send Hagar away?
The text gives the reason explicitly in verse 12: 'for in Isaac shall thy seed be called.' God defines the covenant line through Isaac, so the heir's status must be visibly distinct from Ishmael's. At the same time, in verse 13 God promises to make a nation of Ishmael 'because he is thy seed,' so the expulsion is not a rejection of Hagar's son but a clarification of which line carries the covenant promise. Abraham is comforted that both sons are under God's care, though only one is the heir of the promise.
What is the significance of the well dispute and the seven ewe lambs in verses 25–30?
Abraham reproves Abimelech because servants of Abimelech have 'violently taken away' a well Abraham had dug. Abraham's solution is to set apart seven ewe lambs as a witness that he dug the well, and Abimelech accepts them. The transaction produces a covenant of mutual non-aggression at Beer-sheba ('well of seven' or 'well of oath,' verse 31) and recognizes publicly that 'God is with thee in all that thou doest' (verse 22). The episode functions as a legal and theological marker: Abraham's presence in the land is secured by treaty, and his well becomes the place whose name memorializes both the oath and the sevenfold witness.