¹ The Lord visited Sarah as he had said, and the Lord did to Sarah as he had promised. ² And Sarah conceived and bore Abraham a son in his old age at the time of which God had spoken to him. ³ Abraham called the name of his son who was born to him, whom Sarah bore him, Isaac. ⁴ And Abraham circumcised his son Isaac when he was eight days old, as God had commanded him. ⁵ Abraham was a hundred years old when his son Isaac was born to him. ⁶ And Sarah said, “God has made laughter for me; everyone who hears will laugh over me.” ⁷ And she said, “Who would have said to Abraham that Sarah would nurse children? Yet I have borne him a son in his old age.” – Genesis 21:1-7 ESV

Moses opens this epic chapter with the simple, yet profound words, “the Lord visited Sarah.” After all that has transpired in the preceding chapters, they come across as rather anticlimactic. This is the moment for which Abraham and Sarah have long-awaited and about which they had their fair share of doubts. God had repeatedly promised that Sarah would bear a son, and now the time had come. The long wait was over. The promise was to be fulfilled. And while Moses’ words may lack an air of excitement, they display a strong sense of God’s sovereignty and faithfulness. And three separate times in the first two verses, Moses emphasizes the faithfulness of God.

The Lord visited Sarah as he had said…

…the Lord did to Sarah as he had promised…

And Sarah conceived and bore Abraham a son…of which God had spoken to him…

That simple statement, “and Sarah conceived” is (excuse the pun) pregnant with meaning. God had done the impossible. He had performed a miracle by creating life in Sarah’s lifeless womb. The odds had been against Sarah. When Moses first introduced her in chapter 11, he had declared her unfortunate condition.

Now Sarai was barren; she had no child. – Genesis 11:30 ESV

Yet, in the very next chapter, God had issued His call to Abraham and announced His promise to produce through him and Sarah a great nation. Abraham was 75 and Sarah was 65 at the time. And 25 years later, God had reconfirmed His promise to Abraham.

Then Abraham bowed down to the ground, but he laughed to himself in disbelief. “How could I become a father at the age of 100?” he thought. “And how can Sarah have a baby when she is ninety years old?” – Genesis 17:17 NLT

So, now Sarah’s barrenness was complicated by the curse of fruitlessness that accompanies old age.

Abraham and Sarah were both very old by this time, and Sarah was long past the age of having children. – Genesis 18:11 NLT

And Sarah seemed to believe that her long struggle with infertility had been God’s doing.

So Sarai said to Abram, “The Lord has prevented me from having children.” – Genesis 16:2 NLT

Yet, at just the right moment, according to God’s sovereign plan, Sarah conceived and bore a son. Against all odds and contrary to everything we know about human anatomy and physiology, a 90-year-old barren woman became impregnated by her 100-year-old husband and carried that baby for nine months. And Moses makes it clear that this pregnancy was the work of God. He had done what He had promised to do and He had done it according to His divine timeline. The 25-year delay had been a part of the plan. At no point along the way had God been exasperated by Sarah’s inability to get pregnant. He had not made a mistake in choosing Abraham. Sarah’s barrenness had not been an oversight on God’s part. Even when Sarah and Abraham kept attempting to come up with alternate plans to fulfill God’s promise, He kept reiterating His intentions to use the two of them.

God displayed His power and confirmed His covenant faithfulness through the miracle of Sarah’s pregnancy and her baby’s eventual birth. A year earlier, God had predicted that this moment would come and He had even provided a name for the son who would be born to Abraham and Sarah.

“Sarah your wife shall bear you a son, and you shall call his name Isaac. I will establish my covenant with him as an everlasting covenant for his offspring after him.” – Genesis 17:19 ESV

When Sarah had heard this promise from God, she had reacted with disbelief and scorn, saying, “How could a worn-out woman like me enjoy such pleasure, especially when my master—my husband—is also so old?” (Genesis 18:12 NLT). And God had calmly and patiently responded, “Is anything too hard for the Lord?” (Genesis 18:14 NLT).

Now, God had answered His own question with an irrefutable demonstration of His power that should have clearly ended all speculation regarding His faithfulness. Sarah’s barrenness proved to be no problem for God. Yes, it had caused Sarah great pain and left her questioning the faithfulness and trustworthiness of God. It had frustrated Abraham, causing him to consider and, at times, implement other strategies for becoming the father of a multitude of nations. Both Sarah and Abraham wanted what God had promised, but her barrenness seemed to be an insurmountable barrier to achieving their desire. And a quarter-century of waiting only made matters worse.

But at just the right moment, according to God’s sovereign timeline, the Creator spoke into the darkness of Sarah’s despair and brought about life. And with that life, a light broke into the darkness that permeated Abraham’s world. It would be through this child that God would fulfill His promise to Abraham.

“I will make of you a great nation, and I will bless you and make your name great, so that you will be a blessing.” – Genesis 12:2 ESV

God had clearly promised to do something significant through the offspring of Abraham. He had added, “in you all the families of the earth shall be blessed” (Genesis 12:3 ESV). This boy was destined for great things. And while he would bring great joy and comfort to Abraham and Sarah, he would become the hope of the nations. Through Isaac would come another son, whose birth would also come about through miraculous means. Centuries later, the prophet Isaiah would predict the coming of this child.

Therefore the Lord himself will give you a sign. Behold, the virgin shall conceive and bear a son, and shall call his name Immanuel. – Isaiah 7:14 ESV

And Isaiah would go on to describe the circumstances in which this child would be born.

The people who walked in darkness
    have seen a great light;
those who dwelt in a land of deep darkness,
    on them has light shone.
You have multiplied the nation;
    you have increased its joy;
they rejoice before you
    as with joy at the harvest,
    as they are glad when they divide the spoil. – Isaiah 9:2-3 ESV

The birth of Isaac brought great joy and hope to Abraham and Sarah. And in a similar, yet even more significant way, the birth of this future offspring of Abraham would bring joy to the entire world.

For to us a child is born,
    to us a son is given;
and the government shall be upon his shoulder,
    and his name shall be called
Wonderful Counselor, Mighty God,
    Everlasting Father, Prince of Peace.
Of the increase of his government and of peace
    there will be no end,
on the throne of David and over his kingdom,
    to establish it and to uphold it
with justice and with righteousness
    from this time forth and forevermore.
The zeal of the Lord of hosts will do this. – Isaiah 9:6-7 ESV

At the moment of Isaac’s miraculous birth, the 90-year-old Sarah and her 100-year-old husband found themselves basking in the joy of that momentous and long-awaited occasion. Sarah’s derisive and scornful laughter had been transformed into joyful hilarity at the sight of her miracle baby. As she held her bundle of joy in her arms, she exclaimed, “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 21:6-7 NLT). And the grin on Abraham’s face must have stretched from ear to ear.

What a sense of relief and gratitude this elderly couple must have felt. And you can sense Abraham’s thankfulness in the way he faithfully subjected his newborn son to the God-ordained rite of circumcision.

Abraham circumcised his son Isaac when he was eight days old, as God had commanded him. – Genesis 21:4 ESV

God had done His part, now it was Abraham’s turn. In circumcising Isaac, Abraham was dedicating his son to God. This rite was meant to be a sign of the covenant relationship between God and Abraham’s descendants.

“This is the covenant that you and your descendants must keep: Each male among you must be circumcised. You must cut off the flesh of your foreskin as a sign of the covenant between me and you.” – Genesis 17:10-11 NLT

And God had made it clear that all those who remained uncircumcised would have no part in His future blessings.

“All must be circumcised. Your bodies will bear the mark of my everlasting covenant. Any male who fails to be circumcised will be cut off from the covenant family for breaking the covenant.” – Genesis 17:13-14 NLT

Abraham wasn’t taking any chances. He wasn’t about to curse his newborn son to a lifetime of alienation from God. He had waited too long for this moment and he knew that Isaac was the key to all that God had promised.

“I will make you extremely fruitful. Your descendants will become many nations, and kings will be among them!” – Genesis 17:6 NLT

And though Abraham had no way to comprehend the significance of this promise, the gospel of Matthew provides the future fulfillment to which it pointed.

The book of the genealogy of Jesus Christ, the son of David, the son of Abraham. – Matthew 1:1 ESV

Isaac would be a means to an end. He would be the conduit through which God would bring the ultimate blessing to the nations: Jesus Christ.

English Standard Version (ESV) The Holy Bible, English Standard Version. ESV® Permanent Text Edition® (2016). Copyright © 2001 by Crossway Bibles, a publishing ministry of Good News Publishers.