For the promise to Abraham and his offspring that he would be heir of the world did not come through the law but through the righteousness of faith. For if it is the adherents of the law who are to be the heirs, faith is null and the promise is void. For the law brings wrath, but where there is no law there is no transgression. That is why it depends on faith, in order that the promise may rest on grace and be guaranteed to all his offspring — not only to the adherent of the law but also to the one who shares the faith of Abraham, who is the father of us all, as it is written, “I have made you the father of many nations” — in the presence of the God in whom he believed, who gives life to the dead and calls into existence the things that do not exist. – Romans 4:13-17 ESV
God had promised Abraham that He would bless all the nations of the world through him. But God had a very specific means by which that blessing would come about. In his letter to the church in Galatia, Paul wrote, “God gave the promises to Abraham and his child. And notice that the Scripture doesn’t say ‘to his children,’ as if it meant many descendants. Rather, it says ‘to his child’ — and that, of course, means Christ” (Galatians 3:16 NLT). The means by which God was going to bless the nations was through the coming Messiah, Jesus Christ. It would be through His incarnation, death and resurrection that salvation would be made available to all nations. Did Abraham fully grasp the significance of this promise? Did he understand about the Messiah and God’s future offer of salvation and redemption through His Son’s sacrificial death on the cross. Probably not. But he believed. He trusted God. And the Scriptures say, “And he believed the Lord, and he counted it to him as righteousness” (Genesis 15:6 ESV). The author of the book of Hebrews, in speaking of the faith of the Old Testament saints like Abraham, Moses, David, Abel, Enoch and Noah, writes, “These all died in faith, not having received the things promised, but having seen them and greeted them from afar, and having acknowledged that they were strangers and exiles on the earth” (Hebrews 11:13 ESV). He goes on to say, “And all these, though commended through their faith, did not receive what was promised” (Hebrews 11:39 ESV).
Abraham believed the promise of God even though he did not fully understand it. He never lived long enough to see the promise fulfilled, but he believed that God would do it. And it was that faith in God’s faithfulness that was counted to him as righteousness. Paul’s point in verses 13-17 of Romans four is that God’s promise to Abraham was based on faith not the law. The law had not yet been given when God made His promise to Abraham. And Abraham would not be around when God did give the law to Moses. The promise came long before the law. And the law did not replace or negate the promise of God. Paul makes that point quite clear. “The agreement God made with Abraham could not be canceled 430 years later when God gave the law to Moses. God would be breaking his promise. For if the inheritance could be received by keeping the law, then it would not be the result of accepting God’s promise. But God graciously gave it to Abraham as a promise” (Galatians 3:17-18 NLT).
You can’t have it both ways. There cannot be a way of gaining a right standing before God through the keeping of the law and another way that is based solely on faith. “For if it is the adherents of the law who are to be the heirs, faith is null and the promise is void” (Romans 4:14 ESV). If God’s promise to Abraham he would be blessed and a blessing to the nations was based on the keeping of the law, then there is no place for faith. It is all up to the efforts of men. And it is reserved for the nation to which the law had been given: the Israelites. But Paul breaks the news that the law can only bring wrath. It cannot provide salvation. The law was designed by God to reveal the sinfulness of men. With His law in place, it was impossible for the Jews to plead ignorance. They had no excuse when it came to knowing what God expected of them. But they did have a severe lack of ability when it came to pulling off what the law commanded. So Paul writes, “That is why it depends on faith, in order that the promise may rest on grace and be guaranteed to all his offspring — not only to the adherent of the law but also to the one who shares the faith of Abraham, who is the father of us all” (Romans 4:16 ESV).
Notice that Paul says that our relationship with Abraham is based on our common faith in God, not our adherence to the law of God. God’s promises have always been faith-based. But our faith is not to be in the thing promised as much as in the one who made the promise to begin with. “Now faith is the assurance of things hoped for, the conviction of things not seen” (Hebrews 11:1 ESV). Abraham believed God, even though he could not see or fully understand the things promised by God. He never lived in the land that God had promised him, but he believed in the God who had made the promise. “In hope he believed against hope, that he should become the father of many nations, as he had been told” (Romans 4:18 ESV). All along the way, Abraham had more than enough occasions to doubt, fear, grow anxious and question the faithfulness of God. But Paul declares, “Abraham never wavered in believing God’s promise. In fact, his faith grew stronger, and in this he brought glory to God” (Hebrews 4:20 NLT).
So, “Is there a conflict, then, between God’s law and God’s promises? Absolutely not! If the law could give us new life, we could be made right with God by obeying it. But the Scriptures declare that we are all prisoners of sin, so we receive God’s promise of freedom only by believing in Jesus Christ” (Galatians 3:21-22 NLT). A faith-based promise requires faith in a promise-keeping God.