A sermon on Genesis 15:1-6 and Romans 5:1-11 by Rev Richard Keith on Sunday 7 June 2026
Over the last few weeks we’ve been looking at essential doctrines—the truths of the faith that Christians must believe. We’ve seen that God is good. We’ve seen that God made us good and for our good. And we’ve seen that though we turned away from him into sin and disobedience and have fallen short of the glory for which he made us, God sent his Son Jesus to take our place upon the cross. This then is God’s gift to us: the forgiveness of sins and the promise of eternal life. Salvation by God’s grace, his undeserved kindness, that we receive through faith. God’s salvation becomes ours by means of faith. It’s an essential doctrine. In fact, it’s such an accepted part of Christianity that we often forget how strange it sounds.
The philosopher Bertrand Russell was perhaps the most famous critic of Christianity in the twentieth century. In 1927 he gave a lecture later published as Why I Am Not a Christian, and he put the challenge bluntly. His objection wasn’t simply that faith seemed unfair; it ran deeper. He argued that believing something without sufficient evidence was intellectually irresponsible—that a reasonable person follows the evidence where it leads and stops believing where the evidence runs out.
But he raised a moral question too. If there is a God, and if that God is just, why should a person’s eternal destiny turn on what they believe rather than how they live? Surely what matters is whether a person is kind, whether they are honest, whether they help their neighbour, whether they try to do what is right. Many people today would agree with him: not just atheists or philosophers, but ordinary people who would never call themselves Christians yet try their best and quietly wonder why that wouldn’t be enough.
After all, why faith? Why not good works? Why not sincerity? Why not simply trying your best? For many, faith feels like an arbitrary requirement for salvation. Why should faith matter more than character? Why should the generous neighbour who never darkens the door of a church be worse off than the criminal who turns to Christ in his final hour? Why should believing the right thing count for more than doing the right thing? If God is good, surely he cares more about what sort of people we are than what sort of opinions we hold.
Those are good questions which demand good answers, and the Bible provides them. The search for those answers starts in the book of Genesis. Genesis chapter 15 begins, After this, the word of the Lord came to Abram in a vision: “Do not be afraid, Abram. I am your shield, your very great reward.” Those two words, “after this,” are doing a lot of work. God had first called Abram years before. He told him to leave his country, his people, and his father’s household, and he made him a promise: “I will make you into a great nation.”
It was a wonderful promise. The only problem was that Abram had no children. His wife Sarah was barren, and as the years passed nothing seemed to change. God had promised descendants, but there was still no son. God had promised a nation, but there was still no heir. God had promised a future, but Abram was growing old. Then came famine, hardship, conflict, war—and still no son. By Genesis 15, Abram had every reason to start asking questions. Was God really going to keep his promise? Had he heard God correctly? Could he still trust God’s word?
Abram was in great need of reassurance, which the Lord provided. He came to Abram in a vision and said, “Do not be afraid, Abram. I am your shield, your very great reward.” This is not just the offer of protection from harm but a reminder that the great reward for a life of faith and obedience is God himself. It isn’t wealth or even life forever; God is the reward both in this life and in the next—knowing him, loving him, trusting him, serving him; his presence in all of life’s challenges; his likeness growing within us; seeing him face to face when his kingdom comes. It’s a wonderful promise, and in times of need it can become a prayer that gives strength: God is my shield and my exceedingly great reward.
But God’s promise had not yet answered Abram’s pressing question. Abram replied, O Sovereign Lord, what can you give me since I remain childless and the one who will inherit my estate is Eliezer of Damascus? You have given me no children; so a servant in my household will be my heir. No lightning bolt came down from heaven upon Abram; no rumbling thunder of disapproval from the Lord. God is secure in his divinity; he doesn’t feel threatened by our objections. His ego isn’t undermined by our complaints. He is our heavenly Father and we are always allowed to talk back to him.
At the heart of Abram’s complaint was that he was still childless. The Lord had promised that his descendants would be a great nation, but at that moment Abram had no descendants and the Lord’s great nation had a population of two: Abram and Sarah. As a practical man Abram had made a will; he was rich and someone had to manage his property and look after his widow. Without any reliable close male relative he had chosen one of his servants. So while it was nice to know that the Lord was his great reward, Abram had no child of his own to pass that reward onto. God had promised descendants; Abram remained childless. God had promised a nation, but Abram and Sarah were growing old and the promise seemed impossible.
He could have sulked or held resentful silence, but Abram brought his questions out into the open to the only one who could solve his problem. The Lord replied, “This man will not be your heir, but a son coming from your own body will be your heir.” He took him outside and said, “Look up at the heavens and count the stars—if indeed you can count them.” Then he said to him, “So shall your offspring be.” This was not a rebuke or a demand that Abram stop asking questions; it was an invitation to keep trusting. The Lord restated the promise in more specific terms and vivid imagery: Abram would be a great nation through a child of his own body—flesh of his flesh and bone of his bone.
The Lord reinforced the promise with a display of his wonders. He told Abram to leave his tent and go out into the night to look at the sky and count the stars if he could. It wasn’t a test of Abram’s arithmetic so much as a visual reminder of who was making the promise—the Creator who made the sun, moon, and all the stars, who calls them by name and who governs the heavens. Every star would be a testimony to God’s power to do what he says. Every night henceforth, whenever Abram looked up, the heavens would preach the same sermon: the God who made the stars is able to keep his promises.
Abram had dared to raise his complaint and heard the Lord’s reply, and so he made his choice: Abram believed the Lord, and he credited it to him as righteousness. Abram’s belief was not belief as Bertrand Russell would define it. It was not an opinion stubbornly clung to when evidence ran out, nor a leap into the unknown. Abram’s faith was a leap into the known. It’s like trusting gravity: we don’t declare belief in gravity as a mere opinion; we rely on it because it has proven reliable. That’s what the Bible means by faith. Abram knew he was old and Sarah was barren and the promise seemed impossible, but he also knew who was making the promise. The God who made the stars was able to do what he had said, and Abram put his life in the hands of the one whose word had never failed.
He believed the Lord, and the Lord credited it to him as righteousness. Faith is the beginning of righteousness, and the opposite is true too: distrust is the first step towards sin. We saw that in Genesis 3 when the serpent tempted Adam and Eve—“Did God really say…?”—and cast doubt on God’s motives. Sin didn’t start with a bad action or naughty thoughts; it started with broken trust. Adam and Eve decided God couldn’t be relied upon, so they looked out for themselves. Sin begins with distrust, and faith—trust—is the first step toward righteousness. Faith trusts that God will keep his promises, that God can do what he says, that God has our best interests at heart, and that obedience is best even when we don’t understand why.
Christian faith is centred on our Lord Jesus Christ. If faith is trust in God, nowhere has God shown himself more trustworthy than at the cross. For thousands of years God had been making promises to Abram, to Israel, and through the prophets—promises of forgiveness, salvation, a king, and a kingdom. In Jesus, God kept them. The God who promised Abram a son gave his own Son. The God who promised blessing for all nations brought that blessing through Jesus. The God who promised forgiveness secured it at the cross. The God who promised life vindicated that promise by raising Jesus from the dead.
Abram trusted God’s promise and it was credited to him as righteousness. What was true of Abram is true of us because Abram is our father and we are heirs of God’s promise—not by blood or DNA but by sharing his faith. As Paul says in Romans 5, Therefore, since we have been justified through faith, we have peace with God through our Lord Jesus Christ. We are justified through faith—not by keeping the commandments (because we don’t), not through rituals, but through faith, because our faith is credited to us as righteousness.
It isn’t that God accepts our faith instead of righteousness as if lowering a bar; faith is the first step toward righteousness. God doesn’t want our money or our praise as much as he wants us—every one of us. Our Creator wants a relationship with us and, to restore it when we broke it, he sent Jesus to live, die, and live again for us. Faith is our first step in restoring that relationship. God offers the gift of salvation, forgiveness, and life in his Son Jesus; faith accepts that gift humbly and joyfully.
Faith is the beginning of life with God, walking in the footsteps of Jesus, and it leads to every other blessing. The first and best of these is peace with God: life in the presence of our Creator without fear, resentment, or shame, safe in the knowledge that there is nothing we can do to make God love us more and nothing we can do to make him love us less.