Two Sons, One Offspring

JDudgeon on April 16, 2023
Two Sons, One Offspring
April 16, 2023

Two Sons, One Offspring

Passage: Genesis 21:8-21
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For those who may not know, my name is Josh, and it’s great to see everyone here today—those of you who are regularly here with us, and those who have recently started to join us, as well as those of you who are new or are visiting with us today! I know that many of you are celebrating your loved ones with the rest of the students—especially the graduating class of 2023 at Nipawin Bible College—many of you as proud parents celebrating your children's achievements.

And what I love about Grad Sunday every year is the true reason why everyone comes together to celebrate. I think many of you parents would agree that it’s less about your children’s achievements and more about God’s faithfulness—through the lives of your children and through their growth in Christ over the past year or number of years at NBC—amen? Much celebration and much laughter usually surround this occasion, and much tears are also shed amidst the celebration and laughter.

In more ways than one, this is what our passage today in Genesis 21 is all about. If you haven’t been with us, we have been going through the book of Genesis, and we’ve been waiting for months to get to this chapter that outlines the long-awaited birth of Isaac (21:1-7). Now, in verse 8-21, we hear about the two sons of Abraham, one who was chosen by promise and the other who was cast out of the promise. The first big idea that we will see in this passage is that God Protects Isaac, and our first observation here is that Isaac Grows.

A. God Protects Isaac

I. Isaac Grows (21:8)

“And the child grew and was weaned. And Abraham made a great feast on the day that Isaac was weaned.”

When I thought about this, I couldn’t help but think of a recent example—when Luca stopped breastfeeding. I remember putting my fists in the air, saying: “Yes! My boy is becoming a man!” But I don’t remember putting on a party with everyone to commemorate this seemingly small feat…

You might be asking: why didn’t we hear about this feast at Isaac’s birth? There were certainly hints of celebration in the joyful laughter that Sarah and Abraham shared when Isaac was born, which was manifested in his name—but why put on a great feast at his weaning?Judging by the word “great” and the last time Abraham put on a “quick” feast (Genesis 18:6-8), this was likely an extravagant party!

The best answer to this that many people agree on is that children then were usually breast-fed until about two to three years of age due to the high rate of infancy death at that time (see 1 Samuel 1:22-25), which is the age of Isaac at this point.

With that in mind, it makes total sense that Isaac’s growth from infancy to childhood is a cause for celebration—and it’s also a testament of God’s protection over Abraham’s offspring, in keeping with His promise about Isaac and his offspring after him (Genesis 17:19)!

Yet, any party needs a party pooper, right? Amidst this great feast in celebrating how Isaac has grown, our second observation is that Isaac is Persecuted.

II. Isaac Is Persecuted (21:9)

“But Sarah saw the son of Hagar the Egyptian, whom she had borne to Abraham, laughing.”

The word “but” to start off this verse is evidence enough that there’s something going on here. Yet, the question remains: is there anything wrong with the son of Hagar laughing here? Don’t feasts involve laughter? After all, Sarah’s joyful laughter in response to the miracle birth of Isaac was supposed to be contagious in that “everyone who hears will laugh over [her]” (21:6) and share in this joyful God-given laughter.

So let’s attempt to answer this. The word “laughing” here is the same Hebrew word used in 21:6. Yet, it’s also the same exact word in 19:14 when Lot warned his sons in law about the coming destruction who thought he was “jesting” (or mocking/playing). However, the clearest interpretation of the word usage here comes from the apostle Paul’s explanation in Galatians 4:29: “But just as at that time he who was born according to the flesh [Hagar’s son, Ishmael] persecuted him who was born according to the Spirit {Sarah’s son, Isaac].”

With all this, it’s clear that in Genesis 21, the son of Hagar who was born according to the flesh is laughing in mockery of Isaac—because his baby brother is the miracle baby and the child of promise that’s been long awaited. It’s not a stretch to say that Ishmael did this out of jealousy of Isaac—he would’ve been around 16 years old at this point (16:16; 21:5, 8), so he would’ve been old enough to understand that Isaac is the promised child. Talk about sibling tension…(I mean, my oldest sister was probably jealous of how cute I was—just kidding)!

In fact, pay attention to the narrator’s detail in verse 9 to emphasize the tension at hand: “But Sarah saw the son of Hagar the Egyptian, whom she [Hagar] had borne to Abraham, laughing.” While the happy family of Abraham and Sarah and Isaac is celebrated, Sarah notices that the son of her slave—who was born to her husband—was making fun of her son!

This is why I headlined this second observation as Isaac is “persecuted,” because it helps us capture what’s going on here. This also helps us better understand Sarah’s actions in verse 10. From joyful laughter in celebration to jesting laughter in persecution, our third observation here is that Sarah defends her son.

III. Sarah Defends Her Son (21:10)

“So she said to Abraham, 'Cast out this slave woman with her son, for the son of this slave woman shall not be heir with my son Isaac.’”

Talk about going overboard. Isn’t this just Sarah’s “momma bear” instinct coming out? Some older kid at her son’s party laughs around her son and she gets so defensive about it—to the point of telling her husband, “Get rid of that slave woman and her kid.” After all, Sarah does have a track record of dealing harshly with Hagar and driving her out (16:6)—except this time, she asks Abraham to do it for her.

One important detail that we need to notice here is the continued hints of tension by the author, which is very intentional—notice Sarah’s choice of words in referring to Hagar and Ishmael. Up to this point, every character in the narrative is properly named: Abraham, Sarah, Isaac, including Hagar the Egyptian. Yet, Sarah refers to Hagar as the “slave woman” and Ismael as “her son.”

So whether Sarah’s defensiveness here is warranted or not, we’re about to find out—but what we have found is that this implicit language in play in reference to "the slave and her son” is both intentional and important to the plot—which is further evidenced by our fourth observation when Abraham defends his son.

IV. Abraham Defends His Son (21:11)

“And the thing was very displeasing to Abraham on account of his son.”

There’s that language again, so we must notice the emphasis here. Sarah defends her son (Isaac) in her request to Abraham, yet Abraham found this thing to be very displeasing—because it was on account of his son! That is, his son with Hagar, as opposed to his son with Sarah!

Side note here: in the past, we’ve talked about how the laws against polygamy (multiple marriages) have not yet been given by God at this point in redemptive history, but I hope that we can see the destructive consequences that come from this—which emphasizes the beauty of a monogamous marriage between one man and one woman.

Now, I’m not worried that many people in this room are tempted towards polygamy (though if that’s the case, there’s prayer after the service for you), but I make this side comment as an encouragement for those who are married (including myself) who can be tempted to stray away from being a one-woman man or a one-man woman. I digress.

More importantly, this is the destructive consequence of Abraham taking matters into his own hands by having a child with Hagar instead of waiting on God (and yes, this was Sarah’s idea, but this is ultimately Abraham’s failure because the responsibility was on him as the man in this marriage—just like God held Adam responsible instead of Eve when they sinned in Genesis 3:9).

In his defense, Abraham doesn’t passively give in to Sarah’s request regarding Hagar unlike last time and actually wrestles with the situation—yet, we’ll see in our fifth observation that God steps in to help solve this dilemma in a somewhat surprising way when God affirms Sarah.

V. God Affirms Sarah (21:12)

“But God said to Abraham, ‘Be not displeased because of the boy and because of your slave woman. Whatever Sarah says to you, do as she tells you.’”

I find it ironic that God tells Abraham to do what Sarah says when Abraham finally challenges what she says. Yet, we can’t miss that Sarah’s request is actually in line with God’s Word when she says that “the son of this slave woman shall not be heir with my son Isaac” (21:10)—because in chapter 17, God tells Abraham that the promise of the everlasting covenant was for Isaac and “for his offspring after him” (17:19). Here in chapter 21:12, Sarah’s request affirms God’s Word, so God affirms Sarah in keeping with his word—“through Isaac shall your offspring be named.”

What’s more interesting is the language that God employs here. God echoes Sarah’s unnamed references to Hagar and Ishmael by referring to them as “the boy” and “the slave woman.” In fact, not once will you see Ishmael’s name in this whole passage—which is a clear indicator that only through Isaac shall Abraham’s offspring be named. God makes it clear that Isaac is indeed the child of promise, not Ishmael—the one who must not be named (literally).

In affirming Sarah’s actions, both in her request and reference to those outside the promise, God acts in keeping with his promise. In fact, this whole section on Isaac (as we’ve seen) shows that God protects Isaac in order to keep his promise to Abraham.

Yet, God made other promises to Abraham regarding his son of flesh—so the second big idea that we will see in this passage is that God Protects the Slave Woman and her Son, starting with our first observation in this section when God Assures Abraham.

B. God Protects The Slave Woman and Her Son

I. God Assures Abraham (21:13)

“And I will make a nation of the son of the slave woman also, because he is your offspring.”

When Abraham was first told by God about Isaac’s coming birth in chapter 17, Abraham cries out of concern for the wellbeing of his firstborn: “Oh that Ishmael might live before you!” (17:18). Here, God assures Abraham that his son, the son of the slave woman, will indeed be blessed—in keeping with his promise:

As for Ishmael, I have heard you; behold, I have blessed him and will make him fruitful and multiply him greatly. He shall father twelve princes, and I will make him into a great nation” (17:20).

What’s beautiful about this assurance is that God is keeping his word—through products of Abraham’s lack of faith in his word. The son of the slave woman was a product of Abraham’s lack of faith in God (by the way, Hagar the Egyptian was also a product of Abraham’s lack of faith in God in chapter 12 when he took a detour down to Egypt because a famine hit the land that God told him to dwell in).

Yet, God uses these faithless acts of Abraham for his good purposes and for the good of Abraham. “And we know that for those who love God all things work together for good, for those who are called according to his purpose” (Romans 8:28). Abraham was called by God, and God acts according to his purpose—in keeping with his promise that nations and royalty will come from Abraham (Genesis 17:6), even though Abraham has had an up and down journey of faith.

This time, however, we see that Abraham exercises faith in God’s word and trusts God with his son in our second observation when Abraham Obeys.

VII. Abraham Obeys (21:14a)

“So Abraham rose early in the morning and took bread and a skin of water and gave it to Hagar, putting it on her shoulder, along with the child, and sent her away.”

Now, I hate to cast doubt on our praise of Abraham, but we see both sides of the equation here. On one end, he rises early in the morning and obeys God rather quickly. On another, he gave them bread and a skin of water—which is hardly enough for a trek through the desert.

Now, did Abraham do this because he trusts God to provide for them once they run out of bread and water? Or was he trying to keep his son from being too far from him? Either way, it’s not surprising to see evidence of faith, and the lack thereof, when you look closely at Abraham’s journey of faith.

Nonetheless, the important part is that Abraham does obey and send them away. The banishment of the slave woman and her son was in keeping with God’s promises—separating the two sons of Abraham in order to remove any threat to His promises being kept!

At this point, after Abraham sends them away, it makes total sense to end this section here and continue tracking through Isaac’s story as the child of promise. But that is not the case—this was not the end of the slave woman and her son’s story, because they are still in the scope of God’s purposes in keeping with his promise to Abraham!

So, we shouldn’t be surprised to see the camera pan towards Hagar and her son in our third observation as they wandered in the wilderness.

III. Wandered in the Wilderness (21:14b-15)

“And she departed and wandered in the wilderness of Beersheba. When the water in the skin was gone, she put the child under one of the bushes.”

While the obvious emphasis here is the shortage of water, the bigger emphasis here is the shortage of life itself. The slave woman and her son departed from her source of survival, and they wandered in the wilderness of Beersheba—which was named after a well of water (21:30-31)—where there were no wells to be found.

Life was nowhere to be found, with no signs of survival ahead as they wandered. This is meant to prepare us the fourth observation when we hear about Hagar’s Cry.

IV. Hagar’s Cry (21:16)

“Then she went and sat down opposite him a good way off, about the distance of a bowshot, for she said, ‘Let me not look on the death of the child.’ And as she sat opposite him, she lifted up her voice and wept.”

Not only was the distance of a bowshot opposite her son a long way off, but this language also foreshadows what Hagar expects to happen next—the death of her son. While we might be surprised that she leaves her son on his own, any mother would put her child in the best position of survival—and in this case, it was under the safety of a small shade in the middle of a dry, scorching desert. The closest thing to water at this point were Hagar’s tears.

However, we might be surprised to see in our next observation that instead of Hagar, God Heard The Voice of the Boy.

V. God Heard The Voice of the Boy (21:17-18)

“And God heard the voice of the boy, and the angel of God called to Hagar from heaven and said to her, “What troubles you, Hagar? Fear not, for God has heard the voice of the boy where he is. Up! Lift up the boy, and hold him fast with your hand, for I will make him into a great nation.”

Here, we find out that the boy cried as well. Ishmael’s name means “God hears,” so there’s no shortage of intention here when you connect the dots. God heard the voice of the boy, because of Ishmael—because God hears. But what I find a tad funny about this is the angel’s question for Hagar: What troubles you Hagar?

This could be a question based on her last interaction with the angel of the Lord in the desert (16:7-13). Is this a question of faith? Either way, this was likely more of a statement than a question because Hagar should know that God hears and God sees—after all, that’s what she named God right after God named Ishmael (16:11, 13).

Now, I want to bring attention to the fact that Hagar cries to, and communicates with, God. Whether it was to God or not, Ishmael also cried out—and in both situations, God saw and God heard. It seems an awful lot like Hagar (maybe Ishmael) demonstrates faith in God—so why are they cast out of the promise?

Later on, the Apostle Paul echoes the “slave woman and her son” language in Genesis 21 when he differentiates Hagar and Ishmael form Sarah and Isaac in Galatians 4:21-31, so it’s clear to Paul that they are not included in the promise (and the New Testament authors’ interpretation of the Old Testament has much authority over how we interpret the Old Testament and Scripture today).

But what’s at play here is Paul’s explanation of God’s choice in Romans 9 and the distinction between the children of Abraham: “But it is not as though the word of God has failed. For not all who are descended from Israel belong to Israel, and not all are children of Abraham because they are his offspring, but 'Through Isaac shall your offspring be named.’ This means that it is not the children of the flesh who are the children of God, but the children of the promise are counted as offspring” (Romans 9:6-8).

While Hagar (maybe Ishmael) seemed to have faith in God, she and her son were cast out of the promise because they ultimately didn’t believe in the promise (evidenced by the child of flesh, Ishmael, making fun of the promise and the angel’s question/statement to Hagar). Physical children of Abraham can know God and experience God’s blessings—but only in a physical way. But with Hagar reminded by the God who sees and looks after her, it is fitting that our sixth observation is that God Opened Her Eyes.

VI. God Opened Her Eyes (21:19)

“Then God opened her eyes, and she saw a well of water. And she went and filled the skin with water and gave the boy a drink.”

In the wilderness of Beersheba (wells) where there were no wells of water to be found, the God who looks after Hagar brought her to a well in order to keep her and her son alive. And as we’ve seen already, the God who looks after Hagar is the same God who looks after her son.

We hear this loud and clear in our final observation, God Was With The Boy.

VII. God Was With The Boy (21:20-21)

“And God was with the boy, and he grew up. He lived in the wilderness and became an expert with the bow.

He lived in the wilderness of Paran, and his mother took a wife for him from the land of Egypt.”

The boy grew up (don’t miss the contrasts here with Isaac). The boy lives, but he lives in the wilderness. He survives, but he has to survive with his bow (likely for hunting). He marries, but he marries outside the covenant community of God (16:12).

God was with the boy, but he was far away from God’s promise. As Matthew Henry says, many are full of the blessings of God’s care and providence, yet are strangers to the blessings of God’s covenant and people.

This is where our passage leaves us today. Throughout Genesis 21:8-21, we see that God protects Isaac—in keeping with his promise. At the same time, God protects the slave and her son—in keeping with his promise. Yet, Ishmael’s removal from the line of promise is in keeping with God’s promise, which paves the way for the promise to be fulfilled through Isaac.

But what do these promises mean for us today? Well, when we look through the rest of Scripture, we will see that these are promises for us today—because we know that the promise to Abraham wasn’t ultimately fulfilled through Isaac—instead, it’s fulfilled through the promised offspring that came from Isaac’s line.

C. Promises for Us Today

I. Two Sons, One Offspring (Galatians 3:16)

“Now the promises were made to Abraham and to his offspring. It does not say, ‘And to offsprings,’ referring to many, but referring to one, ‘And to your offspring,’ who is Christ” (Galatians 3:16).

As we always emphasize, Jesus is the main character—not Isaac. The long awaited offspring through Sarah has come, but they had to wait even longer until the promised offspring came at the right time in redemptive history. Here’s what we read this morning in our call to worship: “But when the fullness of time had come, God sent forth his Son, born of woman, born under the law” (Galatians 4:4).

Then, Luke 2 tells us about how the boy Jesus was circumcised and presented to the Lord in the temple according to the Law:

“And when they had performed everything according to the Law of the Lord, they returned into Galilee, to their own town of Nazareth. And the child grew and became strong, filled with wisdom. And the favor of God was upon him” (Luke 2:39-40).

Eventually, he fulfills the law and dies on a cross “to redeem those who were under the law, so that we might receive adoption as sons” (Galatians 4:5) and be brought into the family of God.

This is why Paul, after his spiritual lesson in Galatians 4 based on Genesis 21 with Sarah and Hagar, says that we—like Isaac—are children of promise.

II. Like Isaac, Children of Promise (Galatians 4:28)

“Now you, brothers, like Isaac, are children of promise” (4:28). “And if you are Christ's, then you are Abraham's offspring, heirs according to promise” (3:29).

I hope that most, if not all, of us in this room can confidently say “Amen” to these passages—that we are children of promise like Isaac, brothers and sisters in Christ as Abraham’s offspring.

But if not—maybe you haven’t received Christ or maybe you’re struggling with your faith in Christ—I hope you pay attention to Genesis 21 and the different paths that Isaac and Ishmael take.

Don’t be like Ishmael who, as a child of the flesh, made fun of the child of promise because he didn’t believe the promise. Learn from his mistake that led to him being cast out of the household of promise to wander in the wilderness and survive with his weapons and wells of water.

You, like Ishmael, might be surviving with your own hands instead of trusting in God’s promises—because you’re young and can do anything, or because you have the security of your paycheque and savings account—but one day your hands will give in and that well of water will run out, and the only water that will quench your thirst and help you survive is the living water (John 4:11-15)—which Ishmael rejected.

Instead of Ishmael, consider Isaac. All the more, consider the God of Isaac, who made promises through Isaac, the God who will remove any threat that could get in the way of those promises coming true for Isaac—and it did. It did come true. The promise to Abraham through Isaac came in the person of Jesus Christ, the one offspring of Abraham, who offers that living water welling up to eternal life.

Don’t be blinded by what you see and enjoy now in this life—because everything has an end date. You have an end date when you go down to the grave, so walk by faith and not by sight—because what you really need is someone to bring you out of the grave.

This is why we celebrated Easter last weekend, because Jesus died for you and I and was raised so that we might receive the promise of eternal life. So I implore you to believe in the promises of God—cast out your unbelief or your mere intellectual assent in God and believe in Jesus Christ by faith to be welcomed into the family of God as children of the promise, like Isaac.

But if you are here today and you do believe in the promises of God as children of the promise—brothers and sisters, be encouraged that the God who protected Isaac will keep us safe to the end and give us our promised inheritance in Christ!

As Paul reminds us in Ephesians 1, “in him we have obtained an inheritance…when you heard the word of truth, the gospel of your salvation, and believed in him, were sealed with the promised Holy Spirit, who is the guarantee of our inheritance until we acquire possession of it, to the praise of his glory” (Ephesians 1:11, 13-14).

As we continue to trust in the promises of God, He will remove any hindrances to receiving this imperishable inheritance (1 Peter 1:4), because he has sent the Spirit of his Son in our hearts that cries “Abba! Father!” (Galatians 4:6) as the guarantee of our promised inheritance.

As Paul assures us in Romans 8, “Who shall separate us from the love of Christ? Shall tribulation, or distress, or persecution, or famine, or nakedness, or danger, or sword? No…for I am sure that [nothing] will be able to separate us from the love of God in Christ Jesus our Lord” (Romans 8:35, 37-38). In Philippians 1:6, he says that “I am sure of this, that he who began a good work in you will bring it to completion at the day of Jesus Christ.”

Let’s continue to sing songs like Standing on the Promises and He Will Hold Me Fast, until he comes at last! These songs need to be our life anthem so we can stand firm on God’s promises until that day because brothers and sisters—we will be, like Isaac, persecuted.

III. Like Isaac, Persecuted (Galatians 4:29)

“But just as at that time he who was born according to the flesh persecuted him who was born according to the Spirit, so also it is now” (Galatians 4:29).

Even before Paul, Jesus promised his people that they will be persecuted. But do you remember the second part of that promise?

“Blessed are those who are persecuted for righteousness' sake, for theirs is the kingdom of heaven. Blessed are you when others revile you and persecute you and utter all kinds of evil against you falsely on my account. Rejoice and be glad, for your reward is great in heaven” (Matthew 5:10-12).

NBC Grads, I’m looking forward to celebrating, with you later this afternoon (and I hope to do so with many others in this room), your 3-4 years of faithful perseverance in the Scriptures (and all of those late nights writing papers) as you were equipped to become passionate followers of Jesus Christ with a heart to serve.

But know that the minute you take of that gown today and go your separate ways, know that you are the children of promise like Isaac who will be persecuted by the children of flesh like Ishmael—when you go into your different workplaces (whether it’s this spring and summer or beyond), or into your different churches and communities, or maybe even when you go back into your homes—you will be persecuted like Isaac.

But in those moments, when you’re tempted to flame out because you are mocked and rejected by the world, remember what God did for Isaac. Remember how God protected Isaac in order to keep His promise. Remember that the promises of your older brother, Jesus Christ, in Matthew 5 are for you—so “rejoice and be glad, for your reward is great in heaven!” This is an encouragement for all of us here, whether you’re a student or working or retired, we who are brothers and sisters as children of the promise like Isaac, adopted as sons of God in Christ!

Yet, amidst the persecution, don’t forget God’s heart at the end of Genesis 21 and how he protected the slave woman and her son in the wilderness. Don’t forget the end of Matthew 5—after Jesus promises persecution and the rewards of it—he commands his people to have the same heart as him for their persecutors:

“Love your enemies and pray for those who persecute you, so that you may be sons of your Father who is in heaven. For he makes his sun rise on the evil and on the good, and sends rain on the just and on the unjust” (Matthew 5:44-45).

God makes his sun rise and sends rain on people like Hagar and Ishmael—while they are outside the scope of God’s promises, they are still in the scope of God’s purposes. This includes “unbelievers” and those acknowledge God by mere intellectual assent—yet nothing more. We need to pray for our persecutors in order that their eyes might be opened to the well—not just of physical water that preserves physical life, but of living water that wells up eternal life.

So let’s ask the God of Isaac to give us strength to do this. By faith, let’s stand as children of the promise.

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