Genesis 21:5

KJV

And Abraham was an hundred years old, when his son Isaac was born unto him.

KJV (with Strong's)

And Abraham {H85} was an hundred {H3967} years {H8141} old {H1121}, when his son {H1121} Isaac {H3327} was born {H3205} unto him.

Complete Jewish Bible

Avraham was one hundred years old when his son Yitz'chak [laughter] was born to him.

Berean Standard Bible

Abraham was a hundred years old when his son Isaac was born to him.

American Standard Version

And Abraham was a hundred years old, when his son Isaac was born unto him.

Commentary

### SUMMARY
Genesis 21:5 precisely records the age of Abraham—one hundred years—at the birth of his son, Isaac. This concise statement encapsulates the culmination of decades of divine promise and human expectation, powerfully underscoring the miraculous nature of Isaac’s arrival and the unwavering faithfulness of God to His long-standing covenant pledges, bringing forth life beyond natural human capacity.

### CONTEXT
* **Literary Context:** Genesis 21:5 is situated at a pivotal juncture in the patriarchal narratives, immediately following the fulfillment of God's promise regarding Isaac's birth (Genesis 21:1-3) and preceding Sarah's joyful exclamation and the subsequent events involving Hagar and Ishmael. The preceding chapters, particularly [Genesis 17](/genesis/17 "Genesis 17 - The Covenant of Circumcision and Promise of Isaac") and [Genesis 18](/genesis/18 "Genesis 18 - Abraham's Visitors and Sarah's Laughter"), detail God's repeated assurances to Abraham that he would have a son through Sarah, despite their advanced age. This verse serves as the definitive chronological marker of this long-awaited event, solidifying the miraculous nature of Isaac's conception and birth, which was foretold to occur "at the set time next year" ([Genesis 18:10](/genesis/18-10 "The Promise of Isaac's Birth")). It is a direct and unambiguous declaration of the promise's realization, setting the stage for the unfolding of God's covenant plan through this specific lineage.

* **Historical & Cultural Context:** In the ancient Near East, the ability to produce heirs, especially a male heir, was paramount for a family's legacy, social standing, and economic security. Barrenness was often considered a great misfortune or even a curse, bringing shame upon a woman and her husband. Abraham and Sarah, as a childless couple well past their reproductive years (Abraham was 99 and Sarah around 90 when the promise was reiterated in [Genesis 17:17](/genesis/17-17 "Abraham's Laughter and God's Promise")), faced immense cultural pressure and personal despair. Their situation made the prospect of a natural birth utterly impossible. Therefore, the explicit mention of Abraham's age in Genesis 21:5 is not merely a historical detail but a profound theological statement. It highlights that Isaac's birth was not a natural occurrence but a supernatural act of God, defying all biological and cultural expectations, thereby emphasizing God's unique power and faithfulness to His word.

* **Key Themes:** This verse powerfully contributes to several overarching themes within Genesis and the broader biblical narrative. Foremost is the theme of **Divine Faithfulness and Promise-Keeping**, as God fulfills His word despite human impossibility and long delays. It underscores **God's Sovereignty Over Nature**, demonstrating His ability to transcend natural limitations and bring forth life where it is biologically impossible, asserting His control over creation and human biology. The birth of Isaac at this specific juncture also significantly advances the theme of **Covenant Fulfillment**, establishing the promised lineage through which the Abrahamic covenant would continue and ultimately bless "all the families of the earth" ([Genesis 12:3](/genesis/12-3 "The Abrahamic Covenant - Blessing for All Nations")). Furthermore, it introduces the theme of **Laughter** (the meaning of Isaac's name) as a response to God's work—initially of disbelief ([Genesis 18:12](/genesis/18-12 "Sarah's Laughter of Disbelief")), then of profound joy and wonder ([Genesis 21:6](/genesis/21-6 "Sarah's Joyful Laughter")).

### EXPOSITION AND ANALYSIS
The concise statement of Genesis 21:5, "And Abraham was an hundred years old, when his son Isaac was born unto him," is pregnant with theological significance, marking the precise and miraculous fulfillment of God's long-standing promise.

#### Key Word Analysis
* **Abraham (Hebrew, _ʼAbrâhâm'_):** From אָב and an unused root (probably meaning to be populous); father of a multitude; Abraham, the later name of Abram. The mention of "Abraham" here is crucial, as his very name, meaning "father of a multitude," finds its definitive beginning of fulfillment with Isaac's birth. For decades, this name had been a prophetic declaration awaiting its tangible manifestation, and Isaac's arrival at Abraham's centennial year validates God's naming and His power to bring it to pass.
* **Isaac (Hebrew, _Yitschâq'_):** From צָחַק; laughter (i.e. mockery); Jitschak (or Isaac), son of Abraham. The name "Isaac" itself is a profound commentary on the circumstances of his birth. It encapsulates both Sarah's initial laughter of disbelief when she overheard the promise of a child in her old age, and her subsequent laughter of overwhelming joy and wonder at God's faithfulness. This name serves as a perpetual reminder of the miraculous and joy-filled nature of God's work.
* **born (Hebrew, _yâlad'_):** A primitive root; to bear young; causatively, to beget; medically, to act as midwife; specifically, to show lineage. The verb "was born" (yâlad) here emphasizes the act of bringing forth life. In this context, it highlights a divine begetting, as the natural capacities of Abraham and Sarah were long past. It signifies that this birth was a direct, supernatural act of God, demonstrating His power to create life and fulfill His purposes beyond human limitations.

#### Verse Breakdown
* **"And Abraham was an hundred years old":** This clause immediately establishes the extraordinary context of Isaac's birth. The precise mention of Abraham's age—a full century—is not merely a chronological detail but a theological marker. It emphatically removes any possibility of natural human agency in the conception, highlighting that this birth was entirely a supernatural act of God. It underscores the immense faith required of Abraham and Sarah through decades of waiting and the undeniable miracle of God's intervention.
* **"when his son Isaac":** This phrase identifies the specific, long-promised heir. The name "Isaac" (meaning "laughter") is intentionally included, linking the birth to the earlier divine encounter where both Abraham and Sarah laughed (one in disbelief, the other in amusement/doubt) at the seemingly impossible promise. This son is the tangible beginning of the fulfillment of the Abrahamic covenant, the one through whom the lineage of blessing would continue.
* **"was born unto him":** This final phrase emphasizes the personal nature of this divine gift to Abraham. Isaac was not merely born, but "born *unto him*," signifying that he was the specific, long-awaited heir promised directly to Abraham, the one who would carry on his name and the covenant legacy. It underscores the faithfulness of God in delivering this most precious and personal promise to His servant.

#### Literary Devices
The primary literary device at play in Genesis 21:5 is **Emphasis**, particularly through the precise numerical detail of Abraham's age. By stating "an hundred years old," the text draws immediate and profound attention to the miraculous nature of the birth, leaving no room for doubt that this was a divine act, not a natural occurrence. This numerical emphasis serves to magnify God's power and faithfulness. Additionally, the verse employs **Symbolism** through the name "Isaac" (meaning "laughter"). This name is a symbolic encapsulation of the human response to God's seemingly impossible promise—initially disbelief and amusement, later transformed into profound joy and wonder. The very name becomes a perpetual reminder of the journey from human skepticism to divine fulfillment. The verse also functions as a powerful moment of **Fulfillment**, signaling the culmination of a long narrative arc of divine promise and human waiting, thereby reinforcing the theme of God's unwavering commitment to His word.

### THEOLOGICAL AND THEMATIC CONNECTIONS
Genesis 21:5 stands as a monumental testament to God's absolute faithfulness and His sovereign power over all creation, including the very processes of life. It demonstrates that God's promises are not bound by human limitations or natural laws, but are fulfilled precisely according to His divine will and perfect timing. Isaac's birth, occurring when Abraham was a century old and Sarah was well past childbearing age, unequivocally asserts God's ability to bring life from what is naturally dead or barren. This event serves as a foundational biblical narrative affirming that what is impossible for humans is entirely possible for God, instilling profound hope and encouraging unwavering trust in His word.

* [Romans 4:19-21](/romans/4-19-21 "Abraham's Faith in God's Promise")
* [Hebrews 11:11-12](/hebrews/11-11-12 "Sarah's Faith and the Birth of Isaac")
* [Luke 1:37](/luke/1-37 "With God, Nothing Is Impossible")

### REFLECTION AND APPLICATION
Genesis 21:5 offers profound and enduring encouragement for believers today, reminding us that the God of Abraham is still at work, faithful to His word, even when circumstances seem utterly impossible or the wait is long and arduous. Our human limitations and the apparent unlikelihood of a situation do not, in any way, limit God's power or His capacity to fulfill His promises. This verse calls us to cultivate a deep trust in God's perfect timing, believing that His plans unfold according to His divine schedule, not necessarily ours. It inspires us to persevere in faith in the face of seemingly insurmountable obstacles, knowing that what is impossible for us is entirely possible for God. Furthermore, the joy associated with Isaac's name points to the profound delight and wonder that accompanies the realization of God's promises in our lives, urging us to embrace that joy and give Him glory when His faithfulness is revealed. It compels us to ask ourselves where we are placing limits on God and to instead expand our vision to His limitless power.

#### Questions for Reflection
* **In what areas of your life are you currently waiting on a promise from God that seems impossible to fulfill?**
* **How does Abraham's century-long wait for Isaac encourage you to trust God's timing, even when it differs from your own expectations?**
* **What "laughter of disbelief" might you be holding onto, and how can you allow God to transform it into "laughter of joy" through His faithfulness?**

### FAQ
**Why is Abraham's age so emphasized in Genesis 21:5?**

Answer: Abraham's age of one hundred years is emphasized in [Genesis 21:5](/genesis/21-5 "Abraham's Age at Isaac's Birth") to highlight the miraculous nature of Isaac's birth. It serves as a clear indicator that this was not a natural event but a direct, supernatural act of God. Both Abraham and Sarah were well past childbearing age, making a natural conception biologically impossible. This emphasis underscores God's omnipotence and unwavering faithfulness in fulfilling His promise despite all human limitations, ensuring that the credit for Isaac's existence belongs entirely to Him.

**How does Isaac's birth relate to the Abrahamic covenant?**

Answer: Isaac's birth is a pivotal moment in the fulfillment of the Abrahamic covenant, which God had established with Abraham in [Genesis 12](/genesis/12 "The Call of Abram and the Abrahamic Covenant") and reiterated multiple times. God had promised Abraham countless descendants and that through his seed, all nations would be blessed. Isaac was the specific, promised heir (the "seed" mentioned in [Genesis 17:19](/genesis/17-19 "God's Promise of Isaac Through Sarah")) through whom this covenant lineage would continue. His birth, therefore, was not just a family event but a foundational step in God's grand redemptive plan for humanity, establishing the line that would eventually lead to Christ.

**What is the significance of Isaac's name, "laughter"?**

Answer: The name Isaac (Hebrew: _Yitschâq_) means "he laughs" or "laughter," and its significance is multi-layered. It commemorates both Sarah's initial laughter of disbelief when she heard she would conceive in her old age ([Genesis 18:12](/genesis/18-12 "Sarah's Laughter of Disbelief")), and her subsequent laughter of profound joy and wonder upon his birth ([Genesis 21:6](/genesis/21-6 "Sarah's Joyful Laughter")). The name thus encapsulates the journey from human skepticism and doubt to divine faithfulness and overwhelming joy, serving as a perpetual reminder that God's promises, though seemingly impossible, bring forth ultimate delight when fulfilled.

### CHRIST-CENTERED FULFILLMENT
The miraculous birth of Isaac to Abraham and Sarah in their old age, highlighted in [Genesis 21:5](/genesis/21-5 "Abraham's Age at Isaac's Birth"), serves as a profound and multifaceted foreshadowing of the ultimate Son of Promise, Jesus Christ. Just as Isaac was conceived and born through divine intervention beyond natural human capacity, Jesus Christ was conceived by the Holy Spirit and born of the virgin Mary, transcending all biological limitations ([Luke 1:34-35](/luke/1-34-35 "The Annunciation to Mary")). Isaac was the "son of promise" through whom the covenant lineage and the blessing of Abraham would continue; similarly, Jesus is the ultimate "seed" of Abraham through whom the promise of salvation and blessing extends to all nations ([Galatians 3:16](/galatians/3-16 "Christ as Abraham's Seed")). The seemingly impossible birth of Isaac demonstrated God's power to bring life from a "dead" womb ([Romans 4:19](/romans/4-19 "Abraham's Faith in God's Power")), foreshadowing Christ's resurrection from the dead, which likewise demonstrated God's power to bring spiritual life to those who are spiritually dead ([Ephesians 2:4-5](/ephesians/2-4-5 "Made Alive with Christ")). Thus, Isaac's birth is not merely a historical event but a foundational type, pointing forward to the greater, supernatural work of God in Christ, making possible not just a physical lineage, but spiritual reconciliation and eternal life for all who believe ([John 3:16](/john/3-16 "God So Loved the World")).

Note: Commentary is generated by AI with a directive for Biblical fidelity. Always rely on the Holy Spirit for discernment. The Scripture text and cross-references are from verified, non-AI sources.

Cross-References

Genesis 17:17

Then Abraham fell upon his face, and laughed, and said in his heart, Shall [a child] be born unto him that is an hundred years old? and shall Sarah, that is ninety years old, bear?

Romans 4:19

And being not weak in faith, he considered not his own body now dead, when he was about an hundred years old, neither yet the deadness of Sara's womb:

Genesis 17:1

¶ And when Abram was ninety years old and nine, the LORD appeared to Abram, and said unto him, I [am] the Almighty God; walk before me, and be thou perfect.