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.
In hope he believed against hope, that he should become the father of many nations, as he had been told, “So shall your offspring be.” He did not weaken in faith when he considered his own body, which was as good as dead (since he was about a hundred years old), or when he considered the barrenness of Sarah’s womb.
No unbelief made him waver concerning the promise of God, but he grew strong in his faith as he gave glory to God, fully convinced that God was able to do what he had promised.
That is why his faith was “counted to him as righteousness.”
But the words “it was counted to him” were not written for his sake alone,but for ours also. It will be counted to us who believe in him who raised from the dead Jesus our Lord, who was delivered up for our trespasses and raised for our justification.
We are told by Paul in Romans 4 that Abraham did not “weaken in faith” or “waver” at the promise, yet when you read Genesis you see a lot of wavering. But what we must see is what Paul pointed out about Abraham’s faith here in Romans 4. It grew! He grew in faith! Abraham became fully convinced over time. Abram (“father”) turned into Abraham (“father of a multitude”). As Abraham grew in his faith and continued to give glory to God, he became fully convinced that God was able to do whatever He promised.
You will see below the times Abraham and Sarah wavered as they “grew in faith.”
Genesis 12 – Abraham lied to project himself. There was no need to lie. If God had promised Abraham and Sarah that they would conceive and bear a child, nobody would have the power to kill Abraham.
Genesis 15 – Abraham asked God, “Where is the son you promised me?” God promised Abraham again, and he believed. Genesis 15:6 is often quoted in the New Testament. But notice what happens in the next chapter of Genesis.
Genesis 16 – Abraham and Sarah came up with an alternate plan to bring the promised son into the world. Sarah convinced Abraham to go into her servant girl, Hagar, and have a son. Ishmael was born.
Genesis 17 – Abraham fell on his face and laughed at God’s promise of him and Sarah having a son. He also begged God that Ishmael might be considered the promised son.
Genesis 18 – Sarah also laughed at God’s promise.
Genesis 20 – Abraham lied again to protect himself. See Genesis 12. It was unnecessary to lie. God’s promise of a “multitude of nations” through Abraham showed that Abraham was not going to be killed at that point.
Now, consider what happened after Isaac was born. God asked Abraham to sacrifice Isaac to Him. Look at where Abraham’s faith had come. He did not lie. He did not waver. He did not try to form an alternate plan. He did not fall on his face and laugh and ask for another way. Abraham just did what God said.
But what gave Abraham such strength to offer up Isaac? His strong faith. Look at what Hebrews says about what Abraham’s faith did for him.
By faith Abraham, when he was tested, offered up Isaac, and he who had received the promises was in the act of offering up his only son, of whom it was said, “Through Isaac shall your offspring be named.” He considered that God was able even to raise him from the dead, from which, figuratively speaking, he did receive him back.
By this point, Abraham had such trust in God’s promises that he concluded by faith that if Isaac was killed on that altar, then God would raise him from the dead. That’s incredible faith!
But remember that Abraham did not get to that faith overnight. He grew in faith. Just like you and me. Growth is a process.
I would encourage you to go back over those chapters and take note of all of the great moments of Abraham’s faith. We can list out our failings or moments of weakness in faith, but can we also look back at the times we stood strong in faith? Abraham left everything to go to a strange land (Gen. 12). He showed great humility and generosity to his nephew Lot (Gen. 13). Abraham fought for and rescued Lot (Genesis 14). He trusted in God’s promises (Gen. 15). He obeyed God and was circumcised at 99 years old (Gen. 17)! Abraham showed generosity toward strangers which turned out to be angels (Gen. 18). He prayed for Sodom and Gomorrah (Gen. 18), and he also prayed for Lot (Genesis 19). As you think about Abraham, think about your own faith. You are growing. Don’t just focus on the failings, focus on the victories!