The Promised Son

Genesis 21:1-21

Immanuel – 4/2/23

This is our 14th week following Abraham’s journey of faith. And by God’s design, this 14th sermon dovetails so well into the rhythms of the year, into Palm Sunday. Palm Sunday is a day we remember Jesus’ triumphal entry.

With shouts of “Hosanna,” a great crowd laid palm branches before Jesus, praising God that the Messiah had finally come to Jerusalem. The long-awaited Son had finally arrived. The promises of God were being fulfilled before their very eyes. It was a scene of worship and ecstasy.

Of course, we know that the praises shouted outside of the city would soon take a dark turn inside. In only a few days, before Pontius Pilate, another great crowd would shout, “Crucify Him!” The Messiah would be murdered.

It is as if these two crowds came from two different cities, two different Jerusalems. The two different crowds saw the same Jesus, but their responses could not have been more different.

These exact themes are born in Genesis 21, with another promised son, and with two women who symbolize two different Jerusalems.

Purpose

1. I want you to see the eternal covenant truths woven throughout this passage.

2. I want you to see the ultimate Son of Promise.

Read Genesis 21:1-21

Over 25 years have passed since God first made covenant with Abraham, promising him land and descendants and blessing. Since that moment, Abraham’s journey has been filled with ups and downs, victories and defeats. In the midst of their waiting, time ticks away and promises remain unfulfilled.

He and Sarah begin to worry. God doesn’t seem to be doing anything. So in an attempt to get an heir for Abraham, they take things into their own hands. They agree that Abraham should marry Sarah’s servant, Hagar. The plan works and Hagar bears a son, Ishmael; and with Ishmael is born a conflict that will be felt until the Lord finally closes history – a conflict between faith and works.

Shortly after Ishmael comes of age, at 13, God promises another son, born of Sarah, the son through which the covenant will flow; and his name shall be Isaac. God tells Abraham that Isaac will be born in about a year’s time.

Then narrative of promise and covenant and hope and joy is violently interrupted by a series of disasters: fire in the Valley of Siddim as Sodom and Gomorrah are condemned and turned to ash, Lot descends into scandal and disgrace, Abraham escapes to the wilderness, Sarah is kidnapped and taken into the harem of a foreign king. Right on the eve of fulfillment, God’s promises appear impossible.

But God does not forget His word, and His plans will not fail. He restores Sarah to Abraham, unharmed and unviolated. And just in time. While they are sojourning in Gerar, God visits Sarah.

Read vs 1-2

A Son is Born

When we read God visits Sarah, it does not mean that He sat down with Sarah and they enjoyed tea together. It means that God did something miraculous to Sarah’s 90-year-old womb – and let’s not forget Abraham’s 100-year-old capabilities – and Sarah conceived. It happened at the exact time God had promised.

“I will bless [Sarah], and moreover, I will give you a son by her. I will bless her, and she shall become nations; kings of peoples shall come from her…and you shall call his name Isaac. I will establish my covenant with him as an everlasting covenant for his offspring after him…Isaac, whom Sarah shall bear to you at this time next year.”

-Genesis 17:15-16,19,21

We must see that no amount of human effort could have brought Isaac into the world. In the near disastrous events preceding conception, the circumstances of conception, in the medical impossibility of a 90-year-old carrying to term, in the kings that would rise from Sarah’s womb; it could only be by the hand of God. Where all appeared figuratively dead, God created life.

Read vs 3-4

Abraham names his son Isaac and circumcises him on the eighth day. God has given the promised son. Abraham then acts in covenant obedience as was commanded:

“This is my covenant, which you shall keep, between me and you and your offspring after you: Every male among you shall be circumcised…and it shall be a sign of the covenant between me and you. He who is eight days old among you shall be circumcised. Every male throughout your generations.” -Genesis 17:10,11-12

By circumcising his son on the eighth day, and naming him Isaac as the Lord had said, Abraham is upholding his end of the covenant. But notice, obedience was not required for God to act. God acted first, by giving a son. Obedience was the happy response to God’s faithfulness.

Such is the nature of covenant with God. First God acts, demonstrating his wisdom and power and grace, then we obey him as a joyful response to the wonders He has wrought. Our obedience to God is not forced servitude, our obedience is a free and abounding overflow of worship.

As Abraham and Sarah looked into the face of their impossible baby boy, how their hearts overflowed with joy in God. Naming him Isaac and circumcising him as required was no burden, but a delight.

We see that joy expressed in the very next section.

Read vs 5-7

Remember from chapters 17 and 18, when Abraham and Sarah hear God promise them a son in their old age. Their first response is to laugh. The promise was unbelievable, and they doubted God: “Yea right,” they chuckled. So God told Abraham that the promised son would be named Isaac – Isaac which is a form of the Hebrew word for laughter.

So when Sarah uses the word laughter – twice in verse 6 – it is a pun on Isaac’s name. Her laughter of doubt, and Abraham’s, is now a laughter of astonishment and joy as they hold their precious promised son.

Abraham is the one to officially name the boy, but Sarah is the one who provides its significance. How great the goodness and faithfulness of God!

Look carefully at the working of verse 7. Sarah says, “Who would have said…that Sarah would nurse children?” Children? But Sarah only has one son.

Truly this is a pronouncement of faith! Sarah looks into the eyes of her son and sees the promises of God: that nations would come from him, that kings would be born of his line, that through this boy the earth would be blessed. By faith, as Sarah nurses Isaac, she is nurturing nations.

If Abraham is the father of our faith, Sarah is the mother of it.

So far, in every passage detailing Abraham’s journey, Abraham is the primary speaker. But when the promised son finally arrives, Abraham is silent. It is Sarah who speaks. In Isaac’s birth, Sarah’s covenantal significance has now come to its consummation; and she is foreshadowing glories to come. For when the ultimate Son of promise is born in Bethlehem, it is Mary who erupts in praise: Mary the daughter of Sarah, both the mothers of promise, both the mothers of kings.

But just like when the Christ-child is born, a shadow is soon cast over the joy of Isaac’s birth.

Read vs 8-10

A Shadow

When Isaac was 3-years-old, the traditional age of weaning, Abraham throws a party. But the celebration and joy soon sours. Sarah sees Ishmael laughing – another pun on Isaac’s name. But this is not a happy laughter, this is laughter of mockery. It is sinister; which explains Sarah’s strong reaction.

Remember, in chapter 17, Ishmael came of age at 13-years-old. Then another year elapsed until Isaac was born. Now Isaac is about 3. That puts Ismael around the age of 17. It would seem that Sarah is both scared and angry when she observes this young man scorning her toddler.

But Ishmael’s mockery should not come as a surprise. After Abraham impregnated Hagar, Sarah immediately regretted her plan, and drove Hagar away. There, alone and vulnerable in the wilderness, God spoke promises regarding her unborn son, Ishmael. But mixed into those promises, was a word of warning.

“[Ishmael] shall be a wild donkey of a man, his hand against everyone and everyone’s hand against him, and he shall dwell over against all his kinsmen.”

-Genesis 16:12

Now a young man, God’s warning about Ismael is coming true. He mocks his little half-brother. Referring to this moment, Paul says that Ishmael was persecuting Isaac.

But just as at that time he who was born according to the flesh (Ishmael) persecuted him who was born according to the Spirit (Isaac). -Galatians 4:29

Putting all these pieces together, you get the sense that Ishmael – about 17-years-old – was bullying the toddler: hurting him, ridiculing, laughing about it. And things like this don’t come out of nowhere; they emerge from a preexisting pattern. It’s no wonder that Sarah’s reaction was so strong.

As soon as Hagar gave birth to Ishmael, there was strife between her and Sarah. If there is any confusion, the Bible never condones polygamy (or polyamorous relationships). If nothing else, the Bible again and again reveals that polyamorous relationships are trainwrecks: the corrupted contrivances of man and not according to God’s good design.

Sarah wants Hagar gone, and that rotten son of hers too. She wants to officially, finally, forever, disinherit the both of them. She’s afraid of what Isaac may do down the road and she’s angry at what he’s doing in the present moment. Such is the tone.

Read vs 11-13

It’s easy to sympathize with Abraham’s distress. He loves his son, his firstborn son. However difficult Ishmael may be, it could never erase his love for him.

Perhaps some of you understand that kind of love: love that endures challenges, love that hopes for change, love that follows them as they wander, love that is filled with pain. It’s a reflection of a love found in God. But there does come a time when love needs to be firm.

Then it is Abraham’s turn to be visited by God. The night after the party God visits Abraham, apparently in a dream, and He affirms Sarah’s demand. God tells Abraham to send Ishmael away.

But it’s not a cold condemnation and it is not without hope. God comforts Abraham with a promise. Outside of Abraham’s care, Ishmael will prosper. Ishmael, who bears the covenantal mark of circumcision, will be the father of a nation, of many people. And as tradition would have it, Ishmael is the father of the Arab peoples.

Through Sarah’s demand, God’s plan, and Abraham’s obedience, we are confronted with the stark reality of God’s election. God has always, and will always, choose with whom He will hold covenantal relationship. We do not choose God, but God chooses us.

What shall we say then? Is there injustice on God’s part? By no means! For He says to Moses, “I will have mercy on whom I have mercy, and I will have compassion on whom I have compassion.” So then it depends not on human will or exertion, but on God, who has mercy. -Romans 9:14-16

But remember, God’s election is not without reason. Ishmael’s life is marked by the words we read earlier, “He shall be a wild donkey of a man, his hand against everyone (Genesis 16:12).” That everyone includes God; for to mock the covenant son is to mock God.

Toward the scorners [God] is scornful, but to the humble He gives favor. The wise will inherit honor, but the fool gets disgrace. -Proverbs 3:34-35

In Genesis 21, God’s choice of Isaac over Ishmael is finalized. But despite Ishmael’s obstinacy, and separation from the covenant, God still chooses to bless him. Abraham can do nothing but trust Jehovah-magen with his firstborn.

Read vs 14

A Son of Scorn

The very next morning, Abraham sends his firstborn, with his mother, away. Despite the personal anguish this must have wrought, Abraham’s obedience is complete.

I believe God is using this scene, at least in part, to prepare Abraham for an even greater act of obedience. The time will come when He will ask Abraham not to send Isaac away, but to sacrifice him. Abraham will again demonstrate complete obedience; and it will become the greatest Old Testament picture of the day when God the Father’s sacrificed His one and only Son.

Now sending away his son, Abraham places a bag of provisions upon Hagar’s shoulder. Though Ishmael is about 17, the continual reference to him as a child is a reminder of the relationship he has with his parents. He’s a young man, but to his mother and father, he’s their precious boy.

But alas, as Isaac is weaned from his mother, now Ishmael is weaned from his father. Of the vast wealth of Abraham’s house, the only inheritance given to his son is water and bread put on a shoulder.

Read vs 15-16

At the most, the distance between Gerar and Beersheba is only 20 miles. But like verse 14 says, Hagar and Ishmael wandered. They had nowhere to go. Where could they go? So they wandered, eventually ending up in Beersheba, having exhausted their provisions.

It’s hot in that arid land. With no water left, it wouldn’t take long for dehydration to settle in. The tongue sticks to the roof of the mouth, the head starts to pound, energy evaporates. Hagar directs her son to the shade, at least that may slow the process.

She staggers about a bowshot away, far enough that she cannot hear the cries of her son. She too begins to weep. But they are so dehydrated that it’s likely no tears fall. On the verge of death, with nowhere to go, and no one to help them, it is indeed a hopeless situation.

Her only recourse is to cry out to God, the God of the covenant which she, and her son, have just been expelled from – at least I’m sure that is what it felt like. And there, in that darkest hour, God’s covenantal kindness bursts in.

Read vs 17-18

God speaks to Hagar, affirming the same promise He has spoken to Abraham. They may no longer dwell in the tents of covenant, but because of Abraham’s love for them, God upholds covenantal blessings for Hagar and Ishmael. Ishmael will not die, but he will become a great nation.

How wonderful! God has spoken to Hagar. And this is the second time. When Sarah temporarily banished Hagar back in chapter 16, God first spoke to Hagar. Do you know, there is not one recorded moment where God speaks directly to Sarah? Not once. But He has twice spoken to Hagar.

He will provide.

Read vs 19

One of the effects of severe dehydration is confusion. Perhaps that’s why Hagar did not see the well right beside her. Or maybe God is drawing a merciful parallel.

For in the very next chapter, as Isaac lay on an altar of sacrifice, God will open Abraham’s eyes to a ram stuck in a thicket. A ram that was presumably there all along. Now, with Ishmael on the verge of death, God opens Hagar’s eyes to a well that was there all along. Seeing that her son was dying, suddenly a well of living water. Where there was death, God gives life.

God’s provision and blessing towards Hagar and Ishmael is an enduring reminder that God is willing to extend His grace toward outsiders.

Read vs 20-21

Ishmael will need to become proficient with the bow. If he wants to eat, the wilderness will require it. And if, as the Lord has spoken, his hand will be against everyone, and everyone’s hand against him (Genesis 16:12), he’d better hold a bow in that hand. He will live the rest of his days exiled to the wilderness of Paran.

Hagar, herself an Egyptian (Genesis 16:3), will find for her son a wife from her own people. It’s Hagar’s last act in the narrative of Genesis. We hear no more of her.

Ishmael’s separation is also complete. He’s the son of a slave woman, born from man’s unbelief, cast from covenantal society, married to an Egyptian, remembered for his hostility. Ishmael does not appear again until it is time to bury his father. He is disinherited. The fact that his name is not used once in this whole passage is a final proof that Ishmael is cut off.

Salvation and blessing and relationship with God will only and always come through the son of promise. And if it is already glaringly obvious, the son of promise is most preeminently Jesus Christ.

Read Galatians 4:21-31

2 Mothers = 2 Jerusalems

In the context of Galatians, the law represents the efforts of man. No one can please God, or enter His promises, through achievement. Abraham and Sarah, using Hagar to bear a son, was just that – trying to work their way into the promises of God.

Hagar corresponds to the Jerusalem of self-righteousness; the Jerusalem that tried to achieve righteousness apart from God’s promises. But no one can do this. No one can pick themselves up by their bootstraps and become righteous. All humanity is fallen and wicked. To try to work your way into righteousness is to become a slave – always working, never arriving, perpetually proving your unrighteousness.

The children of Hagar are perpetually bound by desperation, marked by determination and planning. And if someone slightly challenges their self-made position, they are compelled to mock and judge and slight them.

And when the Son of promise is seen, the self-righteous do not want Him, they are blind to their need, and they laugh at Him. They were the Jerusalem that screamed, “Crucify Him!”

But Sarah corresponds to the Jerusalem that is from above – the Jerusalem of freedom and faith. Jesus is that promise: the ultimate promised Son, God’s supreme gift to humanity; the only way, the only truth, the only life. To trust in Him is to be united to Him.

Trusting that all the promises of God find their yes in Jesus (2 Corinthians 1:20), is to enter into covenant blessing. It is to become a child of Sarah. It is to be born again from the Jerusalem that is from above. It is the Jerusalem that cries,

“Hosanna to the Son of David! Blessed is He who comes in the name of the Lord! Hosanna in the highest!” -Matthew 21:9

In Jesus you do not need to prove yourself, Jesus did all the proving for you. When you could not be righteous, He was perfectly righteous. When you deserved to be disinherited and cast into the eternal wilderness, Christ entered that wilderness, overcame it, and flooded it with rivers of living water.

And if Christ has birthed such glories of faith within you, you are now free to rest in the works of Christ. Because of His faithfulness, may it be your joy to live in obedience to Him. Instead of judgment and mockery, allow your heart to be filled with grace and your lips with honor. As Christ has done for you, so you are to do for others.

Finally, brothers and sisters, by trusting Jesus truly did these things on your behalf, you are united to Him and the full inheritance of God is yours.

When the fullness of time had come, God sent forth his Son, born of woman, born under the law, to redeem those who were under the law, so that we might receive adoption as sons. And because you are sons, God has sent the Spirit of his Son into our hearts, crying, “Abba! Father!” So you are no longer a slave, but a son, and if a son, then an heir through God. -Galatians 4:4-7

We are like Ishmael. Jesus is like Isaac. Let us not scorn him. But worship him!

On this Palm Sunday, there is nothing greater you can do than look upon the Son of Promise and cry with all your heart, “Blessed is He who comes in the name of the Lord! Hosanna in the highest!” As Abraham and Sarah looked upon their son of promise, so let your heart be filled with joyous laughter in the presence of Christ – crucified, risen, ascended, and reigning.