From God's Promises to Faith
Perhaps this short description of faith will help.
I became a Christian early in college, and I will never forget the support I found there. I can’t imagine starting my Christian life without those friends, mentors, and church families.
When I went to graduate school, God continued to provide—a wonderful church along with a community of Christian graduate students. A friend who helped lead that group had such an impact on me and my wife that he helped to officiate our wedding.1
This man with a Ph.D. in Biblical studies was a gifted teacher. He could explain complex theological terms and ideas in memorable ways. I don’t think I’ll ever forget his shorthand definition of biblical faith: Faith is trusting God to keep his promises.
This isn’t everything one would want to say about faith. In a classroom setting, we would add context and qualification. But over time I’ve appreciated this definition so much. This friend took years of study and volumes of reading and gave me a sticky way to keep this important term in my brain.
It’s only recently that I think I’ve found the best single passage to defend this short definition.
Faith, Promises, and Grace
The book of Romans is no joke. It is a theological titan among the other books of the Bible.
In Romans 4, after Paul writes about Abraham and justification, he turns to the matter of faith and the promises of God.
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. (Romans 4:13-14)
Imagine how surprised first-century Pharisees must have been by this particular passage. Wait, righteousness doesn’t depend on adhering to the law? No, it comes through faith, and that faith depends on God’s promises.
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)
Further, the promises of God rest on grace. Paul could not be any clearer: faith is key, not obedience to the law.
The God Who Promises
The promise came to Abraham because he believed God (Romans 4:17). Paul connects this belief in God to God’s character and his actions.
Abraham’s God “gives life to the dead and calls into existence the things that do not exist” (Romans 4:17). God’s promises are as sure as the creation on which we are standing. Abraham also knew that God could give life to the dead; when God called Abraham to sacrifice Isaac, Abraham believed (according to Hebrews 11:17–19) God would bring his son back from the dead if needed. This is how sure Abraham was that God would keep his promise.
Abraham trusted God to keep his promises, but he was not believing in a cold legend scratched in stone. God called and spoke to Abraham personally. God met and walked with Abraham, and Abraham knew his character. God is mighty, and he is a promise keeper. Thus, he can (and should) be trusted.
Obstacles Are Not a Barrier
By human measurements, Abraham and Sarah were as likely to have a child as I am (as a slow man of average height in his late 40s) to play professional basketball. Yet these biological facts were not a barrier.
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. (Romans 4:18-19)
Abraham “considered” the natural state of his and Sarah’s bodies, and he considered what “he had been told.” After this consideration, the promises of God carried far more weight.
Abraham was not told how God would keep this promise,2 but he was convinced that he would keep his promise. One thing I love about this paragraph is that there is no reason for us to pretend the human barriers to God’s promise-keeping are absent. God’s promises may seem like the fever dream of a science fiction writer—that’s fine to acknowledge, as long as we acknowledge in the same breath that God is a promise keeper. It is in God’s very nature and character to be faithful to his promises. So, where there seems to be a conflict between God’s promises and what we can imagine or predict, we must side with the sovereign God.
Fully Convinced
Is my friend’s definition of faith the one and only? Probably not. But I hope you’ll agree it is immensely helpful, especially as a starting point. From this passage we know Abraham’s faith was inherently linked to his trust in God to keep his promises.
Would you like to grow in your faith? This passage offers at least one way forward.
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. (Romans 4:20-21)
Abraham became “fully convinced that God was able to do what he had promised.” This caused him to grow “strong in his faith as he gave glory to God.”
As we become more familiar with the Bible, we will see God’s promise-keeping nature more clearly. When we think of him, we will know in our bones that he keeps every promise, despite how things might appear to us. We will praise him, because his faithfulness is a glorious part of his character. And we will, like Abraham, grow strong in our faith.
Hi Bill!
Abraham also was not completely steadfast in his faith either, as Ishmael proves.


