The Isaac Factor
Education for Exultation: Beyond the Possible
He said, "I will surely return to you at this time next year; and behold, Sarah your wife will have a son." And Sarah was listening at the tent door, which was behind him. 11 Now Abraham and Sarah were old, advanced in age; Sarah was past childbearing. 12 Sarah laughed to herself, saying, "After I have become old, shall I have pleasure, my lord being old also?" 13 And the LORD said to Abraham, "Why did Sarah laugh, saying, 'Shall I indeed bear a child, when I am so old?' 14 Is anything too difficult for the LORD? At the appointed time I will return to you, at this time next year, and Sarah will have a son." 15 Sarah denied it however, saying, "I did not laugh"; for she was afraid. And He said, "No, but you did laugh."
God Requires the Impossible - the Gideon Venture
You recall from last week that God's purpose was to give the Midianites into the hand of Gideon. Gideon had an army of 10,000 men. Arrayed against him were Midianites and Amalekites as numerous as the sands on the seashore. So God did something very typical for God and very atypical for man. "The LORD said to Gideon, 'The people who are with you are too many for Me to give Midian into their hands, for Israel would become boastful, saying, "My own power has delivered me"'" (Judges 7:2).
It already looked impossible for Israel to defeat the Midianites with only 10,000 men against so many. But God said, "Ten thousand is too many." Why? Because my purpose is to display my glory, and help you see how utterly dependent you are on sovereign grace.
This is the purpose of God in all that he does in creation and redemption. God's purpose in all that he does is:
To magnify his sovereign grace And keep us in our humble place.
And one of the central beliefs that we have as God's people is that this is good news, not bad news. It is good news because God himself, known to us in Jesus Christ, is more valuable and more satisfying than anything we could ever be or do in our own power. The most loving thing that God can do for us is to make himself indispensable to us. The most loving thing God can do for us is not to make much of us, but to work by his sovereign grace so that we can enjoy making much of him forever. So, if he would love us, he must exalt his sovereign grace and keep us in our humble, happy place.
That's the point of the Gideon Venture. That is why God over and over and over again in the Bible does things in a way that makes us utterly dependent on God for what is humanly impossible - to magnify his sovereign grace and keep us in our humble place.
God Does the Impossible - the Isaac Factor
This morning's message is simply to point to another Bible story and how it illustrates this truth. It's the story of the birth of Isaac, the son of Abraham and Sarah, the child of promise. Let's get some of the details of the story in front of us.
According to Genesis 11:30, Abram's wife was barren even before they came to the Promised Land. "Sarai was barren; she had no child." This was not merely coincidental. It was planned by God. We know this because in Genesis 16:2 Sarah said, "The LORD has prevented me from bearing children." So God is putting in place circumstances that will make the fulfillment of his promise humanly impossible.
What promise? The promise that Abraham would have many offspring and become a great nation. Genesis 12:2, "I will make you a great nation, and I will bless you, and make your name great; and so you shall be a blessing." That promise came after the knowledge that Sarah was barren. Indeed, God had closed her womb, and then made the promise. So now, if Abraham believes the promise, it will be a believing not just in the ability of God to predict the future, but in the power of God to create a future that is humanly impossible.
This is what I call "The Isaac Factor": God's purpose to do what is humanly impossible, so that we have to trust his power and grace, and he gets the glory. But we do not naturally trust God so easily. It goes against our fallen nature. Here's what usually happens: When we meet a situation like this, we try to think of ways that we can actually make it happen by ordinary human means.
Let's watch this in Abraham's life. The first natural thought he has is that God may fulfill his promise to make him a great nation (Genesis 12:2) by raising up heirs to him through his slave, Eliezer. God has to set Abraham straight here and make sure he sees how impossible he really means the promise to be. Look at Genesis 15:2-4.
Abram said, "O Lord GOD, what will You give me, since I am childless, and the heir of my house is Eliezer of Damascus?" And Abram said, "Since You have given no offspring to me, one born in my house is my heir." Then behold, the word of the LORD came to him, saying, "This man will not be your heir; but one who will come forth from your own body, he shall be your heir."
So God cuts off Abraham's escape. No, Abraham, my promise will not be fulfilled in the humanly possible way of using your slave as your legal heir. My way will be humanly impossible: You will become a great nation through your own physical seed - your own biological son.
God's Requirement for Us - Faith
What does God require from Abraham? He requires that Abraham believe him, trust him. So God takes Abraham outside and says to him in verse 5, "Now look toward the heavens, and count the stars, if you are able to count them." And He said to him, "So shall your descendants be." Then verse 6 says that "Abraham believed in the LORD; and [God] reckoned it to him as righteousness." That's the faith that corresponds to "The Isaac Factor".
But there is one more escape hatch from God's sovereign grace and the humanly impossible promise. God has only said that the son of promise would come from Abraham's body (Genesis 15:4), not from Sarah's body. So what about using a concubine to get the promise to come true?
Let's watch what happens when Abraham and Sarah try this. Genesis 16:1-2: "Now Sarai, Abram's wife had borne him no children, and she had an Egyptian maid whose name was Hagar. So Sarai said to Abram, 'Now behold, the LORD has prevented me from bearing children. Please go in to my maid; perhaps I will obtain children through her.' And Abram listened to the voice of Sarai.'" Verse 15: "So Hagar bore Abram a son; and Abram called the name of his son, whom Hagar bore, Ishmael. Abram was eighty-six years old when Hagar bore Ishmael to him."
This was not God's plan for how his promise would be fulfilled. God's promise was going to depend on sovereign grace, not on human ingenuity. Ishmael was not the son of promise, precisely because he was humanly possible.
Look at Genesis 17:15-16 to see what God says about this. The time is about thirteen years later. God comes to Abraham and says, "As for Sarai your wife, you shall not call her name Sarai, but Sarah shall be her name. I will bless her, and indeed I will give you a son by her." This was a great setback to Abraham. He thought he had a human way figured out to have heirs from his own body just as God said he would.
Now God says, No, I will do it the impossible way, Abraham. So Abraham's faith wavered for a moment and Genesis 17:17 says, "[He] fell on his face and laughed, and said in his heart, 'Will a child be born to a man one hundred years old? And will Sarah, who is ninety years old, bear a child?'" And he pleaded with God to fulfill his promise in a less spectacular way. Verse 18: "Abraham said to God, 'Oh that Ishmael might live before You!' But God said, 'No, but Sarah your wife will bear you a son, and you shall call his name Isaac; and I will establish My covenant with him for an everlasting covenant for his descendants after him.'"
Why Won't He Settle for the Humanly Possible?
Why? Why won't God opt for anything less than the path of impossibility? I think he tells us in the next chapter (Genesis 18:10-14). God comes to Abraham and makes the promise again:
"I will surely return to you at this time next year; and behold, Sarah your wife will have a son." And Sarah was listening at the tent door, which was behind him. Now Abraham and Sarah were old, advanced in age; Sarah was past childbearing [not only barren all her life, but now passed childbearing years]. Sarah laughed to herself, saying, "After I have become old, shall I have pleasure, my lord being old also?" And the LORD said to Abraham, "Why did Sarah laugh, saying, 'Shall I indeed bear a child, when I am so old?' Is anything too difficult for the LORD?"
There it is. That's the reason God will not settle for anything less than the path of impossibility: He aims to show that nothing is too difficult for the Lord. His purpose in all he does is
To magnify his sovereign grace And keep us in our humble place.
This is "The Isaac Factor" - and it is exactly what God did. Genesis 21:1-3: "Then the LORD took note of Sarah as He had said, and the LORD did for Sarah as He had promised. So Sarah conceived and bore a son to Abraham in his old age, at the appointed time of which God had spoken to him. Abraham called the name of his son who was born to him, whom Sarah bore to him, Isaac."
God planned and worked in a way that made the promise to Abraham humanly impossible. 1) He saw to it that Sarah was barren from the beginning. 2) He refused the human solution of a legal heir named Eliezer. 3) He rejected the human solution of having sex with Hagar to beget Ishmael. 4) He waited till Abraham and Sarah were old and she was beyond childbearing years before the child of promise was born. 5) And he predicted the very time of the child's birth.
Implications for Us
In all these ways God acted to make clear that sovereign grace, not human initiative, brings about children of promise. Now let me apply this to us in two ways.
1. The first is that each of us who is a child of God - a member of his saved covenant people, an heir of God's promise - became what we are by sovereign grace, not human initiative.
You can see this application in Romans 9:6-9. Paul is wrestling with the heartache that many of his fellow Jews are not believing in Jesus Christ, the Messiah, and are therefore perishing (Romans 9:3). Does this mean that God's promise to his Jewish people has failed? He answers in verse 6, "It is not as though the word of God has failed." How does he explain this? He says in verse 6b, "For they are not all Israel who are descended from Israel; (7a) nor are they all children because they are Abraham's descendants." In other words, to be an heir of the promises made to Abraham you can't just be the product of ordinary human reproduction.
Then he goes right to our story of Isaac and the way Isaac came into being to show what he means. He says in verse 7b, "But: 'THROUGH ISAAC YOUR DESCENDANTS WILL BE NAMED.'" In other words, "Not Ishmael, the fruit of your human self-reliance, but through Isaac the child whom I brought into being when it was humanly impossible." Then Paul states the general principle that he is drawing out of the story. Verse 8: "That is, it is not the children of the flesh who are children of God, but the children of the promise are regarded as descendants."
What is the difference between a "child of the flesh" and the "children of promise"? The difference is that ordinary human resources bring children of the flesh into being, but the sovereign power of God's promise brings the children of promise into being. You see this in verse 9: "For this is the word of promise: 'AT THIS TIME I WILL COME, AND SARAH SHALL HAVE A SON.'" In other words, Abraham tried to make an heir for God's promise by the human initiative, that is, out of flesh (Ishmael), but God said, "No, heirs of promise come into being through supernatural, divine intervention. That is what it means to be a Christian - an heir of God's covenant promises. That is how you became a Christian.
Know this. Cherish this. Be thankful for this with all your heart. Be humbled by this. This is "The Isaac Factor."
God magnifies his sovereign grace And keeps us in our humble place.
2. Finally, the second application is to the funding of Education for Exultation. Is it possible that we could enter a $9 million educational and multi-purpose building in two years, debt-free? The answer we offer is simply the word of God to Abraham in Genesis 18:14, "Is anything too difficult for the LORD?"
Our hope and prayer is that God, in his great mercy, would look upon our plan not as presumption but as one more expression of the great Isaac Factor that runs through the whole Bible: God often does things in a way that makes us depend on him for the humanly impossible. Why?
To magnify his sovereign grace
And keep us in our humble place.
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