Heb 6:13–17 — God's Unbreakable Oath

The Promise and the Oath

This is a wonderful passage in Hebrews—one of my favorites. It is a declaration of the certainty of the promise of God confirmed by an oath in which God swore an oath, not only to Abraham, but to us, guaranteeing the truth of the promise of the gospel. The title of the sermon is God’s Unbreakable Oath. The text mentions there in verse 18 that there are two unchangeable things. What are those two unchangeable things? The two unchangeable things are first, the promise that God made, and then the oath that he gave to confirm that promise and to guarantee it and to add certainty to it. God does not need to add that certainty.

His word is good enough, but we need that. We need that assurance and that confidence. It is amazing when you read this passage of wonderful comfort concerning God’s unbreakable oath and his promise of the gospel to us, his people. It is amazing to think about the context in which this passage appears. It is only a few verses after that passage that we looked at two weeks ago. The threatening passage where the author of this letter warns the congregation, which we argued was a mixed congregation, not everyone in the congregation was a genuine believer, and he warns the congregation that it is impossible In the case of those who have tasted the truths of the gospel, who have become connected to the truths of the gospel through membership in the church and through baptism, if they reject that, if they turn away from it and reject Christ, it is impossible to restore them again to repentance. And so that is a very solemn warning passage that is very threatening.

It is warning the people of God do not think that everything is well just because you are physically there in the body of the church, just because you are in the membership of the church. Are you trusting in Christ? Are you persevering in faith? Or are you about to turn away from the Lord?

Many of the members of this congregation were tempted because of the pressure of the persecution from their Jewish friends and neighbors who did not believe in Jesus. They were under pressure to go back to their former Jewish way of life and to deny Christ, even though they had once professed him.

The author of Hebrews says, do not do that. Do not fall away. Because if you do, you are crucifying, once again, the son of God to your own harm. You are holding him up to contempt. He was saying, although I once professed Jesus and his death on the cross for my sins, I now despise this Jesus. I think that he should indeed have been crucified. And it is as if they are going back again to the crowd in Jerusalem, shouting, crucify him, crucify him.

We also pointed out that the impossibility there that is mentioned in the text should not be taken in a metaphysical sense, as if it is impossible for someone to be forgiven if they repent. The Lord will always forgive those who turn to him in humble faith and repentance. The impossibility is a moral, it is a spiritual impossibility. If someone has come this close to knowing the Lord, has become this connected to the things and the truths of the gospel, and then turns against that and hardens their heart against it, then it is practically, morally, spiritually impossible for them to repent. If you have someone in your life who once professed to know the Lord and now is walking away from the Lord, do not give up on them. You can still pray for them and ask that they would repent and come back to the Lord. But there is a particular case of, in the context here, of someone who turns against the Lord in such a high-handed and contemptuous way that it makes it practically impossible for them to repent. That is the issue that is being dealt with there in that passage.

But the author of Hebrews, after making this solemn warning, do not fall away from Christ, do not turn against the gospel that you once professed, then turns in this passage to a wonderful encouragement, an encouragement that is just as glorious and just as encouraging as the warning. The warning is very threatening and very solemn, but the encouragement outweighs that with its glorious call to persevere in the Lord.

The author of Hebrews says in verse 11, we desire each one of you to show the same earnestness to have the full assurance of hope until the end. We want you to have an earnest zeal to persevere in your faith in the Lord Jesus Christ. Do not be sluggish. But rather the imitators of those who through faith and patience inherited the promises. Referring to not only their forefathers in the faith, whoever it was that planted this church and the leaders of the church, but also going back to the Old Testament times like Abraham and all the saints. The author of Hebrews is going to mention more of those in Hebrews chapter 11. When he talks about the hall of faith and all the wonderful examples of the Old Testament believers who persevered in faith in spite of the obstacles, in spite of all the trials and tribulations. And who inherited the promises by patiently trusting in God.

God Swore by Himself

So the author of Hebrews then wants to encourage his audience. He says, although this warning is solemn and severe, yet he says, although we speak this way, we have confidence that these things are not true of you and that you are believers. And so we are encouraging you to do not be sluggish, but rather continue in the faith. Persevere in the faith and the author of Hebrews then points to the example specifically of Abraham and the way in which he received the promises and trusted in those promises and also the way in which God added to those promises, the oath guaranteeing and confirming those promises, he points to Abraham as the great example to encourage us to have that same faith in the promises of God. So in verse 13, when God made a promise to Abraham, since he had no one greater by whom to swear, he swore by himself. He swore by himself.

Now the quotation that is given there in verse 14, surely I will bless you and multiply you, is from Genesis chapter 22. Genesis 22, which is a little bit later in the story of Abraham. The story of Abraham begins in Genesis 12, when God first calls Abraham out of Ur of the Chaldeans. But in Genesis 22, quite some time has passed. He has already been through lots of trials and tribulations and tests of his faith. And in Genesis 22, we have the greatest test of all, when God told Abraham to offer his son Isaac as a sacrifice to the Lord. And Abraham obeyed the Lord.

Abraham was willing to do that. Of course, the angel intervened before he actually took the knife and killed his son and said, now I know that you truly trust me. And it is at this point that our author is quoting from Genesis 22, verse 16. Which says that the angel of the Lord called to Abraham a second time from heaven and said, by myself I have sworn, declares the Lord.

Now did you hear that phrase there? By myself I have sworn. And the word swear means to swear an oath. By myself I have sworn an oath. Declares the Lord, because you have done this and have not withheld your son, your only son, I will surely bless you and I will surely multiply your offspring as the stars of heaven and as the sand that is on the seashore.

The author of Hebrews then is quoting that part. He does not quote that phrase, by myself I have sworn, but he does allude to it when he says in verse 13, that because God had no one greater to swear by, he swore by himself, saying, surely I will bless you and multiply you. But the text itself in Genesis 22, verse 16 says, by myself, I have sworn, declares the Lord. Now you might think that because the author of Hebrews is directly quoting from Genesis 22, that he is referring specifically to this moment here alone. He is only referring to this incident when Abraham was about to offer up his son, and then God said, by myself I have sworn, God declares the Lord. But we should not stop at that surface level.

There are also reasons to see an allusion to some earlier episodes in the story of Abraham, in the narrative of Abraham’s life, going back to Genesis 12 and also Genesis 15. What are some reasons to see that? Genesis 12 is the initial call where he comes out of Ur of the Chaldeans and God sends him into the land. God says, I will bless you, give you this land to your offspring. Genesis 15 is the passage when God swears an oath again.

The content of the promise that is given here in Genesis chapter 22 is a repetition of the promises that were already uttered and repeated in Genesis 12 and Genesis 15 without any substantial difference. That helps us then to confirm that the author of Hebrews is not only looking at Genesis 22 and the story of the offering of Isaac. He is looking back to this whole story of Abraham’s life with God in which God was progressively repeating to him these promises and reiterating them again and again. Another thing that helps us to see that there is a connection to these earlier passages in Genesis is the fact that we already mentioned in verse 18, when the author of Hebrews refers to two unchangeable things, clearly referring to the promise, which was initially made in Genesis 12, and to the oath. Which is added to the promise.

The explicit oath language is only used in Genesis 22, by myself I have sworn an oath, but the oath itself was made and acted out in Genesis 15. Would you turn in your Bibles to Genesis 15 to see that story? In Genesis chapter 15, it says, after these things, this is after the rescue of Lot, and the blessing of Abraham by Melchizedek, which the author of Hebrews is going to talk about next in Hebrews chapter seven. But after these things, the word of the Lord came to Abraham in a vision. Fear not, Abram, I am your shield. Your reward shall be very great.

But Abram said, here is the problem is that God has made these great promises to Abraham, but it does not seem like they are coming true. He has not had a child yet. Abraham said, Oh Lord God, what will you give me? For I continue childless and the heir of my house is Eliezer of Damascus. We had a house servant who was like a steward who ran the household. And he is thinking, well, if God is not giving him his own son, then maybe, maybe this servant here will be the heir. And Abraham 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. Someone who will come from your own body, not just a household servant that you can appoint to be the heir. Your own son will be your heir. And he brought him outside and said, look toward heaven and number the stars if you are able to number them. And he said to him, so shall your offspring be.

And Abraham believed the Lord and he counted it to him as righteousness. Of course, the apostle Paul will quote that particular verse several times in his epistles in Romans and Galatians and say, that is the gospel right there. Abraham believed in God’s promise. And by faith alone he was counted as righteous in the sight of God.

But it continues on. This is the interesting thing. God has made this promise and Abraham has believed it, even though the promise does not seem like it is coming true just yet. But there is an interesting thing that happens here as Abraham continues to wrestle with God. He believes, he believes the promise, but he wants some confirmation. He wants some added guarantee.

How can I know, Lord? God says to him, he repeats to him, I am the Lord who brought you out from Ur of the Chaldeans to give you this land to possess. But Abraham said, verse eight, oh Lord God, how am I to know that I shall possess it? How can I know? How can I have assurance? And so what does God do? God says, I am going to give you an added confirmation of this promise. And so what he does is he acts out the swearing of an oath, but he acts it out in a physical way.

God says to Abraham, go bring me a heifer, three years old, a female goat, three years old, a ram, three years old, a turtle dove and a young pigeon. And so Abram brought him all these and cut them in half so the animals were slaughtered. And he laid each half over against the other, but he did not cut the birds in half. And when birds of prey came down on the carcasses, Abram drove them away. Birds of prey symbolizing the curse of death.

So this is a very solemn thing that is being done here. A solemn acting out, not of the promise, but of the oath to confirm the promise. Verse 12, as the sun was going down, a deep sleep fell on Abram. And behold, a dreadful and great darkness fell upon him. This is a very solemn scene, full of fear and the curse, the birds of prey, the darkness. This is the curse of God. Then the Lord said to Abram, know for certain that your offspring will be sojourners in a land that is not theirs and will be servants there.”

That is referring to when they go down to Egypt and they are servants of Pharaoh and the Egyptians. And they will be afflicted for 400 years. But I will bring judgment on the nation that they serve, referring to the Exodus when they come up out of Egypt. And the 10 plagues that God sent upon the Egyptians. And afterward, they will come out with great possession. As for you, you shall go to your fathers in peace. You shall be buried in a good old age, and they shall come back here to this land in the fourth generation, for the iniquity of the Amorites is not yet complete.”

And then here we have the key moment when God takes the oath. Verse 17, when the sun had gone down and it was dark, behold, a smoking fire pot and a flaming torch passed between these pieces. God himself in the form of a theophany, in the form of a smoking fire pot and flaming torch, God himself passes between the pieces of the carcasses of the animals that had been slaughtered.

The Oath That Settles the Dispute

And on that day, the text says, the Lord made a covenant with Abram. The Lord cut a covenant by cutting the animal pieces and then by passing through them himself. In doing so, God is saying to Abraham, this covenant that I am making with you is guaranteed by my very self, by my very existence. That is what God is referring to in Genesis 22, 16, when he says, by myself, I have sworn, declares the Lord. By myself, I was the one that passed between those pieces. I was the one that was saying, may I be under the curse and judgment And this covenant, therefore, is confirmed and ratified by an oath. God, in visible form, passes between the sacrificial animal pieces. And in this way, he is confirming the truth of his promise.

The Gospel Promised to Abraham

Remember, Abraham had said, I would like some assurance. I believe you, Lord, but how can I know for sure? So the Lord says, here is how you can know for sure. And our text then in Hebrews 6 verse 15 says that, thus, Abraham, having patiently waited, obtained the promise, which I think alludes to the time period between Genesis 15 and the birth of Isaac in Genesis chapter 21, and then the offering of Isaac in the next chapter. There is a long period of time where Abraham is waiting. It does not seem like it is coming true, but Abraham is trusting in the Lord. He is patiently waiting and obtaining the promise by putting all of his trust and reliance in God and in God alone.

God’s oath. Was self-determined. He swore by himself. When men swear an oath, they swear by something greater than themselves, on my mother’s grave, or something greater than themselves that they think will add weight and certainty to their oath. But with God, there is no one in heaven or on earth greater than God. And so when God swears, he swears by himself. The oath is grounded in God’s own self-existence, his immutable, unchanging self-existence. This oath cannot be broken any more than God himself can cease to be God.

So God’s promise is absolutely guaranteed. It is certified. There is the promise itself, and then there is the stamp of approval, the seal, the guarantee that says this promise is certain. If it were up to Abraham and his faithfulness to the Lord, the promise would be broken. We see throughout the story how Abraham fails again and again. He tried to, of course it was his wife’s idea, but he tried to go into Hagar, his wife’s maid servant, and thought maybe I could raise up offspring through that.

That was not what God had said. God had said, it is going to come from your very own body. God said, you have to trust in me and not try to take matters into your own hands and do it through your own fleshly abilities. He disobeyed the Lord many times. He lied about his wife being his wife and said that she was his sister, even though that was partly true because she was a distant relative. All of these things, Abraham continued to fail and disobey the Lord and prove that he was faithless.

And yet God is saying, this promise is so guaranteed that I, God is saying, I will take upon myself the obligation to deal with the punishment for the breaking of this covenant. God himself will pass between the pieces. Of course, pointing ahead to Christ himself, who on the cross bore the wrath of God in our place. We were the ones that broke the covenant. We were the ones that were unfaithful to the Lord, but he took upon himself the punishment that we deserved.

How wonderful it is to know that this oath cannot be broken any more than God himself can cease to be God. And if it is broken on our side, even that too, God will take up the obligation for the punishment and God himself will guarantee that the promise comes true in spite of our failures and in spite of our sins.

There is a wonderful statement there in verse 17 that I would like to drill down on a little bit more. It says, so when God desired to show more convincingly to the heirs of the promise the unchangeable character of his purpose, he guaranteed it with an oath. That last phrase there, God wanted, remember Abraham asked, Lord, how can I know? And so when God desired to show more convincingly to the heirs of the promise, including Abraham, including us, the unchangeable character of his purpose, he guaranteed it with an oath. That word that is translated guaranteed. Is hard to render exactly.

It is from a verb that is the verb form of the word mediator. For example, in Hebrews 8, verse 6, it says that Jesus is the mediator of the new covenant. Hebrews 8, Christ has obtained a ministry that is as much more excellent than the old as the covenant he mediates is better since it is enacted on better promises. And again, in chapter nine, verse 15, he is the mediator of a new covenant so that we might receive the eternal inheritance. The word that is translated guaranteed is related to that word mediator. Maybe it could be translated as mediated. He mediated with an oath. He arbitrated, he settled the dispute with an oath. There is not really a dispute here between God and Abraham, but there is a mild dispute. There is this sense of Abraham saying, Lord, I would like to have certainty. I would like to know for sure. And so God himself intermediates to settle this question, to settle this sense of doubt on Abraham’s part.

This choice of this verb is intentional, I believe, because it is calling to mind that Christ is the mediator of the new covenant. When it says he guaranteed it with an oath, he intermediated with an oath, it is almost as if Christ himself is the oath. And that is not too far-fetched, is it? Because when you consider that God himself passed between the animal carcasses, and undertook the curse of the breaking of the covenant on our part.

That is pointing ahead to the cross of Christ. He became a curse for us. Just think of all the things in that passage in Genesis 15 that remind you of the crucifixion scene. Remember the darkness? It talks about the darkness and the dead of night. Same with Christ. When he was on the cross, it was dark. The darkness covered the land because it was the wrath of God that was coming upon the Son of God who was bearing it for us in our place.

It is that not far-fetched then to think that in our text, the author of Hebrews is subtly using this language to say that he intermediated with an oath and the oath is Christ himself, the one who fulfills that passage in Genesis 15, when God himself took the oath and took the curse upon him for us to confirm the truth of the gospel.

God’s promise to Abraham is not simply an analogy for the gospel and for the Christian life and how we are to trust in God just like Abraham did. When God made the promise to Abraham and then confirmed it with that oath, with God himself enduring the curse and making the oath confirmed by his own passing between the pieces as a picture of the cross of Christ, when God did that, that was The gospel. Not just an analogy for the gospel as if Abraham had a similar thing like the gospel and then we come along later and we have a similar relationship to God. And so just as Abraham looked to the oath that God made to him, so also we look to Jesus Christ and the promise that he has confirmed to us through his death.

The author of Hebrews is saying that this is the gospel. This is the very same thing that Paul says. Remember in Galatians chapter 3 where the Apostle Paul says in verse 8 that the gospel was preached beforehand to Abraham? And Abraham believed that gospel. And so we too, if we belong to Christ, are Abraham’s offspring and heirs according to the promise.

Notice how our author here, not Paul, but someone like Paul, probably from the Pauline circle, someone like Apollos or Barnabas or one of Paul’s coworkers, this author also speaks of us in the same language as the Apostle Paul, that we are heirs of the same promise.

We are heirs of the same promise. It is not a different promise. We are heirs of it. And so this promise is for us. And the author of Hebrews goes on to speak of Christ as our great high priest and how his death on the cross and then his ascension into heaven is the confirmation of God’s promises to us. The author of Hebrews is using this narrative from the Old Testament and the story of Abraham in Genesis 12 and 15 and 22, not merely as an analogy or as an example or a sermonic illustration of what it means to live the Christian life. He is using it as a direct application to us. God wants us to follow in the same footsteps of Abraham and to believe in God’s promise and to trust in him.

There are many people today who believe that the reconstitution of the nation of Israel in 1948 was the fulfillment of this promise and of this oath that God made to Abraham. And so the nation of Israel today is enjoying the fulfillment, enjoying the fulfillment of this promise. God made a promise to Abraham, to your offspring, I will give this land.

And now the nation of Israel is experiencing the fulfillment of that promise and of that oath to them. How that robs us of the truth of the assurance of the gospel to take it that way and to apply it incorrectly to a modern nation. Even more striking is the fact that most of the Israelis today do not believe in Jesus as the Messiah. Yes, there are a small number of Messianic Jews, but most of the citizens of the nation of Israel reject Jesus as the Messiah? How could it be that by rejecting Christ, or as our author would say, by crucifying him again, how could they be inheriting and receiving the promises that God made that are fulfilled only in Christ?

Strong Encouragement for Weak Faith

It is crystal clear in our text in Hebrews chapter six and throughout the scriptures, including Paul’s teaching in Galatians and so on, that God’s promise to Abraham was the gospel of Christ. And all those who believe in Jesus Christ and who put their trust in him are the recipients of this oath. We are the ones who are the heirs of God’s promise. That does not mean that the Jews are excluded. Even the Jews too, if they believe in Jesus as the Messiah, can receive these same promises by faith in Him. But the key is that it does not come apart from Christ. The only way to receive this assurance and this strong encouragement and to know that the inheritance belongs to you is by believing in Christ and trusting in Him.

I think it is marvelous in our text to observe how it says that God desired to show more convincingly to the heirs of the promise the unchangeable character of his purpose. God desired. God wants us to have certainty. God desires to show to his people more convincingly the certainty of the gospel promise. The adding of this oath and this ceremony of going through the pieces, which points ahead to the cross of Christ, was not necessary on God’s part. It was added entirely for our benefit to make it crystal clear that God is committed to fulfilling his promise.

He is committed to showing how certain and unbreakable his promise is. God is aware of the fact that we struggle. He is aware of the fact that we have doubts. And he so lovingly condescends. Look at how he treats Abraham when Abraham says, Lord, I believe, but I would like to have some assurance. I would like to know for sure. He does not dismiss that request. He does not say, Abraham, my promise is good enough. Why are you doubting me? God condescends to Abraham’s desire for absolute unshakable certainty.

So he condescends to us as well. He knows the frailty of our faith. He knows our doubts. He knows how we struggle to believe that the gospel is true, that we really are forgiven. And so he wants us to have assurance. He does it to give us strong encouragement. And just like Abraham, where throughout his life that God comes to him again and again, repeating the promises over and over again. And he patiently perseveres through all of the struggles with doubt. He continues to go back to the promise and to trust in the Lord.

We see that is the way it is for us too in the Christian life. The Christian life is not always triumphant. It is not always living on the heights of Zion and rejoicing in the Lord every day. There are times of struggle. There are times of doubt. There are times of temptation. There are times when we just do not really feel it. We just feel kind of blah. We do not really feel the power of the truths of the gospel.

But the key is, as our text says in verse 15, Abraham patiently waited. He patiently endured. He continued to go back again to the promises of God and to lay hold of those promises. Even when he failed, even when he sinned, he continued to go back. The Lord wants us to do that as well. The great danger is that not we have struggles. The great danger is that we, as the author of Hebrews says, turn away from Christ and reject him altogether. That is the great danger. Never grow tired, never grow weary of coming to church on Sunday and hearing again the assurance of God’s pardon and being reminded again of the truths of the gospel. I think that is one of the reasons why the Lord gave us as his people communion as a weekly reminder of the truths of the gospel. Communion is like that oath that God made to Abraham.

It is a visible sign and seal that confirms the truth of the gospel. Heidelberg Catechism puts it this way, what are sacraments? Question 66, sacraments are visible, holy signs and seals. They were instituted by God so that by our use of them, he might make us understand more clearly the promise of the gospel and seal that promise.