“If we emphasize faith does that mean we can forget about the law?” Paul asks at the end of Romans 3. And then he answers himself: “Of course not! In fact, only when we have faith do we truly fulfill the law.”
It seems to me that the first 4 chapters of Romans are primarily about sin, law and faith and the relationship between all three. And up to now we have learned that we all sin, that the law doesn’t help but instead just makes the sin more obvious and that faith is somehow the answer to it all. Paul has also introduced the concept of grace/ undeserved favour. In chapter 4 Paul tries to explain faith using Abraham as an example.
First of all it is as well to establish that Abraham was a sinner. He mistrusted God on at least two occasions we know of and put Sarah in a compromised position, he had a child by his wife’s servant – as well as several other liaisons. He also committed murder on several occasions – or at least he was involved in war – and would have killed his own son if God hadn’t stopped him (Genesis 22). By the way, it looks like Sarah had had enough after that incident since we don’t see her with him again until she is dead. You wouldn’t blame her for not wanting to stay with a man who said God told him to kill their son.
But the Scriptures tell us, “Abraham believed God, and God counted him as righteous because of his faith.” Romans 4:3). Abraham, just like us, needed a saviour – a God who forgives sinners. And it was the trusting relationship with God that enabled God to pass on that forgiveness to him. There was no way he could be with God, believing God, and not be forgiven since he couldn’t stand before God’s holiness except in a place of forgiveness.
“Oh what joy for those whose disobedience is forgiven, whose sins are put out of sight. Yes, what joy for those whose record the Lord has cleared of sin!” as David says (Psalm 32: 1-2 quoted in Romans 4:7.8). Another man who needed a saviour.
The death of Jesus looks back as well as forward in its effects.