Summary: The birth of Isaac in Genesis 21:1-7 teaches us to rejoice in God's faithfulness in fulfilling his promise by miraculously calling Isaac into existence.

Scripture

When Abraham was seventy-five years old, God called him out of Ur of the Chaldeans to go to the Promised Land, which God was giving to him. God also promised to make of Abraham a great nation (Genesis 12:2). However, the problem was that Abraham’s wife, Sarah, “was barren; she had no child” (Genesis 11:30). So, how could God make a great nation of Abraham when his wife was infertile?

After Abraham arrived in the Promised Land, he continued on to Egypt. When he came back, his nephew Lot separated from him and went to the beautiful Jordan valley. Then God met Abraham and said to him in Genesis 13:16, “I will make your offspring as the dust of the earth, so that if one can count the dust of the earth, your offspring also can be counted.”

After many years of waiting, Abraham complained to God. We read in Genesis 15:2–5, “But Abram said, ‘O Lord God, what will you give me, for I continue childless, and the heir of my house is Eliezer of Damascus?’ And Abram said, ‘Behold, you have given me no offspring, and a member of my household will be my heir.’ And behold, the word of the Lord came to him: ‘This man shall not be your heir; your very own son shall be your heir.’ And he brought him outside and said, ‘Look toward heaven, and number the stars, if you are able to number them.’ Then he said to him, ‘So shall your offspring be.’” This was now the third time that God had promised offspring to Abraham.

When Abraham was eighty-five years old, and his wife Sarah was seventy-five years old, she came up with a different plan. God had promised offspring to Abraham, but he had never clearly stated that the offspring would be with his wife Sarah. In those days, the custom was for the husband to produce children through his wife’s servant. So, Sarah gave her Egypt servant, Hagar, to Abraham so that he could produce a child. The plan worked. Hagar became pregnant, as we read in Genesis 16:15, “And Hagar bore Abram a son, and Abram called the name of his son, whom Hagar bore, Ishmael.” Moses added in Genesis 16:16, “Abram was eighty-six years old when Hagar bore Ishmael to Abram.”

The problem appeared to be solved. Abraham had a son just in time, in his old age. As far as Abraham and Sarah were concerned, God had fulfilled his promise to Abraham, and had given him a child. For the next thirteen years, Abraham and Sarah seemed to be content with the situation.

However, Abraham and Sarah’s plan was not God’s plan. Genesis 17:1a says, “When Abram was ninety-nine years old the Lord appeared to Abram.” Now, for the first time, God made it clear that the promised child was to come through Sarah, as he said in verse 16, “I will bless her, and moreover, I will give you a son by her.” Abraham could not believe his ears! What? A son by Sarah who was ninety years old? And he himself was a hundred years old? Verse 17 says, “Then Abraham fell on his face and laughed and said to himself, ‘Shall a child be born to a man who is a hundred years old? Shall Sarah, who is ninety years old, bear a child?’” Abraham’s laughter was a laugher of incredulity. By now, it was physically impossible for him to have children, and Sarah, although barren, was also far too old to bear children. So, Abraham pleaded with God in verse 18, “Oh that Ishmael might live before you!” But God replied, “No, but Sarah your wife shall bear you a son” (Genesis 17:19a).

A short time later, God appeared again and reiterated his promise of a son to Abraham by Sarah. This time Sarah overheard God speaking, and she laughed to herself, saying, “After I am worn out, and my lord is old, shall I have pleasure?” (Genesis 18:12). Sarah’s laughter was also a laughter of incredulity. But God said, “Is anything too hard for the Lord? At the appointed time I will return to you, about this time next year, and Sarah shall have a son” (Genesis 18:14).

Now, let’s read about the birth of Isaac in Genesis 21:1-7:

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)

Introduction

Many people take their membership in the church of Jesus Christ for granted. Some even consider their membership a burden. Far too many professing Christians simply do not understand the importance and necessity of church membership.

God’s people in the Old Testament also frequently failed to appreciate the miracle of belonging to God’s covenant family. And yet, the very existence of the people of God was a miracle of God. Twenty-five years after receiving the promise of a son, God gave Abraham and Sarah a son, whom they named Isaac.

Lesson

The birth of Isaac in Genesis 21:1-7 teaches us to rejoice in God’s faithfulness in fulfilling his promise by miraculously calling Isaac into existence.

Let’s use the following outline:

1. Isaac’s Miraculous Birth (21:1-7)

2. Jesus’ Miraculous Birth

I. Isaac’s Miraculous Birth (21:1-7)

First, let’s look at Isaac’s miraculous birth.

Isaac’s birth was announced in Genesis 21:1-7 in a brief and matter-of-fact way. However, it was a very significant event in God’s covenant with Abraham. Let us notice seven significant features in Isaac’s miraculous birth.

A. Isaac’s Birth Was the Result of Divine Activity (21:1a)

First, Isaac’s birth was the result of divine activity.

Verse 1a states, “The Lord visited Sarah….” The Hebrew word for visited (paqad) is interesting. One dictionary states, “The basic meaning is to exercise oversight over a subordinate, either in the form of inspecting or of taking action to cause a considerable change in the circumstances of the subordinate, either for the better or for the worse.” Clearly, God took action to cause a considerable change in the circumstances of Sarah. She was barren, and she was far beyond the years of being able to bear children. Strictly speaking, Isaac’s birth was not miraculous. Rather, it was his conception that was miraculous, and it was the result of divine activity.

B. Isaac’s Birth Happened Exactly as God Had Promised (21:1b-2)

Second, Isaac’s birth happened exactly as God had promised.

Three times Moses emphasized that truth. We read in verses 1-2, “The Lord visited Sarah as he had said, and the Lord did to Sarah as he had promised. And Sarah conceived and bore Abraham a son in his old age at the time of which God had spoken to him.” At times, Abraham and Sarah doubted God’s promise. In fact, they took things into their own hands and produced a son, Ishmael, through Sarah’s servant, Hagar. But Ishmael was not the promised son. God was faithful in spite of their lack of faith. Isaac’s birth happened exactly as God had promised.

Let us learn to trust the promises of God to us. Let us not have a lack of faith.

C. Isaac’s Birth Arrived at the Right Time in God’s Plan (21:2b)

Third, Isaac’s birth arrived at the right time in God’s plan.

In Genesis 17:21 God said to Abraham, “But I will establish my covenant with Isaac, whom Sarah shall bear to you at this time next year.” This promise was repeated in Genesis 18:14, “Is anything too hard for the Lord? At the appointed time I will return to you, about this time next year, and Sarah shall have a son.” Verse 2 of our text says, “And Sarah conceived and bore Abraham a son in his old age at the time of which God had spoken to him.”

James Montgomery Boice notes:

One of the hardest things we face in life is what seems to us to be delays in God’s actions. We pray. The answer is delayed. Then we fume and fret and sometimes set about to work out the answer for ourselves. What is wrong when we do this? Simply put: We are not trusting. We are doubting either God’s ability to do what he has promised or God’s timing. We need to trust God and wait upon him.

D. Isaac’s Birth Was Miraculous (21: 2, 5, 7)

Fourth, Isaac’s birth was miraculous.

Verse 2 says, “And Sarah conceived and bore Abraham a son in his old age….” Verse 5 says, “Abraham was a hundred years old when his son Isaac was born to him.” And in verse 7, Sarah said, “Who would have said to Abraham that Sarah would nurse children? Yet I have borne him a son in his old age.” “Humanly speaking,” said Boice, “there was no possibility at all that Abraham could have a child at this age. But although this was impossible with men, with God all things are possible. God is sovereign, and he can do what he will in his universe.”

Some of you may say that this miracle was only for Abraham and Sarah. God would not do that for you. Your situation is different than theirs. Well, it is true that your situation is different. But God is not different. God is still sovereign. God is still all-powerful. God is still able to fulfill all of his Word to you.

E. Before His Birth, Isaac Was Named by God (21:3)

Fifth, before his birth, Isaac was named by God.

In Genesis 17:19 God said to Abraham, “No, but Sarah your wife shall bear you a son, and you shall call his name Isaac.” So, in obedience to God, “Abraham called the name of his son who was born to him, whom Sarah bore him, Isaac” (21:3).

Abraham’s obedience is important. By now, Abraham knew that he should trust God fully and completely. And he did so by obeying God’s command to name his son, Isaac.

Similarly, we have God’s written Word. We should fully and completely obey all that is in God’s written Word.

F. Isaac’s Birth Brought Much Joy (21:6)

Sixth, Isaac’s birth brought much joy.

In verses 5-6 we read, “Abraham was a hundred years old when his son Isaac was born to him. And Sarah said, ‘God has made laughter for me; everyone who hears will laugh over me.’”

Earlier, in Genesis 17:19, God had said that they were to call their son “Isaac.” The name Isaac means, “laughter.” The very name of the promised son would remind Abraham and Sarah that initially their laughter was a laughter of incredulity. It was simply impossible for a hundred-year old man and his barren, ninety-year old wife to conceived and have a child. But, the laughter of incredulity gave way to a laughter of inexpressible joy.

G. Isaac Was Circumcised When He Was Eight Days Old (21:4)

And finally, Isaac was circumcised when he was eight days old.

God had commanded the sacrament of circumcision in Genesis 17:12, “He who is eight days old among you shall be circumcised.” So, “Abraham circumcised his son Isaac when he was eight days old, as God had commanded him” (21:4).

The miraculous birth of Isaac was proof to Abraham of God’s ability to keep his word. Isaac’s birth also anticipated the One in whom all the promises of God find their fulfillment. The significant features surrounding Isaac’s miraculous birth would have helped Abraham and Sarah look forward to the Greater Isaac, Jesus.

II. Jesus’ Miraculous Birth

Second, let’s briefly examine Jesus’ miraculous birth.

There are remarkable similarities between Isaac’s miraculous birth and Jesus’ miraculous birth. Let us notice seven significant features in Jesus’ miraculous birth.

A. Jesus’ Birth Was the Result of Divine Activity

First, Jesus’ birth was the result of divine activity.

You know the story. Jesus was conceived by God the Holy Spirit in his mother Mary before she had any intimate relations with a man. Matthew 1:18 says, “Now the birth of Jesus Christ took place in this way. When his mother Mary had been betrothed to Joseph, before they came together she was found to be with child from the Holy Spirit.”

B. Jesus’ Birth Happened Exactly as God Had Promised

Second, Jesus’ birth happened exactly as God had promised.

When Joseph, Mary’s betrothed found out that she was pregnant, he decided to cancel the wedding. However, Matthew 1:20–23 says, “But as he considered these things, behold, an angel of the Lord appeared to him in a dream, saying, ‘Joseph, son of David, do not fear to take Mary as your wife, for that which is conceived in her is from the Holy Spirit. She will bear a son, and you shall call his name Jesus, for he will save his people from their sins.’ All this took place to fulfill what the Lord had spoken by the prophet: ‘Behold, the virgin shall conceive and bear a son, and they shall call his name Immanuel (which means, God with us).’”

C. Jesus’ Birth Arrived at the Right Time in God’s Plan

Third, Jesus’ birth arrived at the right time in God’s plan.

The Apostle Paul made this clear when he wrote to the Galatians in Galatians 4:4, “But when the fullness of time had come, God sent forth his Son, born of woman.”

D. Jesus’ Birth Was Miraculous

Fourth, Jesus’ birth was miraculous.

Again, like Isaac, Jesus’ birth was natural. It was his conception that was miraculous. Matthew 1:18 says, “Now the birth of Jesus Christ took place in this way. When his mother Mary had been betrothed to Joseph, before they came together she was found to be with child from the Holy Spirit.”

E. Before His Birth, Jesus Was Named by God

Fifth, before his birth, Jesus was named by God.

The angel of the Lord told Joseph that Mary’s baby was to be called “Jesus.” Matthew 1:21 says, “She will bear a son, and you shall call his name Jesus, for he will save his people from their sins.” So, in obedience to God, that is exactly what Joseph did, as we read in Matthew 1:24–25, “When Joseph woke from sleep, he did as the angel of the Lord commanded him: he took his wife, but knew her not until she had given birth to a son. And he called his name Jesus.”

F. Jesus’ Birth Brought Much Joy

Sixth, Jesus’ birth brought much joy.

Many people rejoiced at the birth of Jesus. Even before his birth, Mary, the mother of Jesus said, “My soul magnifies the Lord, and my spirit rejoices in God my Savior” (Luke 1:46–47). Later, after his birth, the angels announced “good news of great joy that will be for all the people” (Luke 2:10). The shepherds, Simeon, and Anna praised God when they saw Jesus (Luke 2:20, 28-32, 38). And the wise men from the east rejoiced when they saw the star that led them to Jesus, and they worshiped him (Matthew 2:1-12).

G. Jesus Was Circumcised When He Was Eight Days Old

And finally, Jesus was circumcised when he was eight days old.

Luke 2:21 says, “And at the end of eight days, when he was circumcised, he was called Jesus, the name given by the angel before he was conceived in the womb.”

Conclusion

Therefore, having analyzed the birth of Isaac in Genesis 21:1-7, we should rejoice in God’s faithfulness which miraculously called us into existence as the Lord’s special people.

I have compared Isaac’s miraculous birth with Jesus’ miraculous birth. But there is also a comparison between Isaac’s miraculous birth and the spiritual birth necessary for any person to be saved and become a child of God. Paul said to the Romans in Romans 4:18–25, “In hope [Abraham] believed against hope, that he should become the father of many nations, as he had been told, ‘So shall your offspring be.’ He did not weaken in faith when he considered his own body, which was as good as dead (since he was about a hundred years old), or when he considered the barrenness of Sarah’s womb. No unbelief made him waver concerning the promise of God, but he grew strong in his faith as he gave glory to God, fully convinced that God was able to do what he had promised. That is why his faith was ‘counted to him as righteousness.’ But the words ‘it was counted to him’ were not written for his sake alone, but for ours also. It will be counted to us who believe in him who raised from the dead Jesus our Lord, who was delivered up for our trespasses and raised for our justification.”

Let us believe in him who raised from the dead Jesus our Lord. And let us rejoice in God’s faithfulness which miraculously called us into existence as the Lord’s special people. Amen.