What is faith?
Question 7052
Of all the words we use in the Christian life, faith is surely one of the most common and yet one of the most misunderstood. We sing about it, we preach about it, we’re told we need more of it, but what actually is it? Is it a feeling? A leap in the dark? Simply believing hard enough? The world has its own ideas about faith, but what does the Bible say? Getting this right matters enormously, because Scripture tells us that without faith it is impossible to please God (Hebrews 11:6), and that we are saved through faith (Ephesians 2:8). So let’s open up the Scriptures and see what faith really is.
The Biblical Definition of Faith
The classic definition of faith comes from Hebrews 11:1, which reads: “Now faith is the assurance of things hoped for, the conviction of things not seen” (ESV). The Greek word here is πίστις (pistis), and it carries the sense of trust, confidence, and firm persuasion. The writer to the Hebrews isn’t giving us an abstract philosophical definition but rather showing us what faith does and how it operates. Faith gives us ὑπόστασις (hupostasis), translated “assurance” or “substance” — a word that speaks of something solid, a foundation, a confident certainty. And faith provides ἔλεγχος (elegchos), translated “conviction” or “evidence” — the inner certainty of realities we cannot see with our physical eyes.
Think about it this way: faith is not pretending that something is true when deep down we’re not sure. It’s not whistling in the dark. Rather, biblical faith is a settled confidence in God and His Word, a trust that what He has said is absolutely reliable, even when we cannot see the full picture. It is treating as real the things that God has promised, even though we haven’t yet experienced them in their fullness. The whole of Hebrews 11, that great chapter often called the “Hall of Faith,” gives us example after example of men and women who lived on this basis — Abraham leaving his homeland not knowing where he was going, Moses choosing to suffer with God’s people rather than enjoy the pleasures of Egypt, and many others who “died in faith, not having received the things promised, but having seen them and greeted them from afar” (Hebrews 11:13).
Faith Is Not a Blind Leap
One of the great misunderstandings about Christian faith is that it means believing without evidence, a sort of blind leap into the unknown. Nothing could be further from the truth. Biblical faith is not opposed to evidence; it is built upon evidence. When God called Abraham, He gave him promises and confirmed them with a covenant. When Jesus performed miracles, He said these works bore witness to who He was (John 10:25, 38). When Paul preached the resurrection, he appealed to the testimony of hundreds of eyewitnesses (1 Corinthians 15:3–8). Faith responds to revelation. It is a trust in God based on what God has made known about Himself.
The apostle Peter, writing to believers scattered across the Roman world, said: “Though you have not seen him, you love him. Though you do not now see him, you believe in him and rejoice with joy that is inexpressible and filled with glory” (1 Peter 1:8). These believers had not seen Jesus with their own eyes, yet their faith was not groundless. They had the testimony of the apostles, the witness of the Scriptures, the work of the Holy Spirit, and the evidence of transformed lives. Their faith was trust based on reliable testimony, not wishful thinking.
The same is true for us today. We believe in Jesus not because we have physically seen Him, but because we have been given overwhelming evidence — the historical record of Scripture, the testimony of the resurrection, the fulfilment of prophecy, the witness of the Spirit, and the ongoing work of God in the lives of His people throughout history. Faith is indeed the conviction of things not seen, but those unseen things are not unknown. God has revealed them to us in His Word.
The Three Elements of Saving Faith
Theologians down through the centuries have helpfully identified three elements that make up genuine saving faith, and it’s worth understanding these because they help us see what true faith involves and what it is not.
The first element is knowledge (in Latin, notitia). You cannot believe in something you know nothing about. Faith requires content. We must know certain facts: that we are sinners, that Jesus is the Son of God, that He died for our sins and rose again, that salvation is found in Him alone. Paul puts it plainly in Romans 10:14: “How then will they call on him in whom they have not believed? And how are they to believe in him of whom they have never heard?” This is why the preaching of the Gospel is so essential — people need to hear and understand the message before they can respond to it. Faith is not a vague religious feeling; it has definite content rooted in the truths of Scripture.
The second element is assent (in Latin, assensus). This means agreeing that the facts are true. It’s one thing to know what the Gospel says; it’s another to believe that it is actually true. Many people know what Christianity teaches but do not believe it is genuinely the case. Assent involves accepting these truths as real, as corresponding to reality, as reliable. But here’s where we must be careful, because assent by itself is not enough. James tells us that “even the demons believe — and shudder!” (James 2:19). The demons know that God exists, they know who Jesus is, and they acknowledge these facts as true. But that is not saving faith.
The third element — and this is where saving faith goes beyond mere intellectual agreement — is trust (in Latin, fiducia). This is personal reliance upon Jesus, entrusting ourselves to Him, resting our whole weight upon Him for salvation. It’s the difference between knowing that a chair can hold your weight and actually sitting down in it. It’s the difference between knowing the lifeboat can save you and actually getting into it. Saving faith means coming to Jesus, receiving Him, depending on Him alone for forgiveness and eternal life. Jesus Himself said: “Come to me, all who labour and are heavy laden, and I will give you rest” (Matthew 11:28). Faith is responding to that invitation, coming to Him, and resting in Him.
This is why the New Testament so often speaks of believing in or into Jesus — the Greek preposition εἰς (eis) conveys movement toward and into, a personal commitment and union with Him. John 3:16, that most famous of verses, tells us that “whoever believes in him should not perish but have eternal life.” It’s not just believing that Jesus exists or that certain things about Him are true; it’s placing our trust in Him as Saviour and Lord.
Faith and Works: Getting the Relationship Right
If there’s one area where confusion abounds, it’s the relationship between faith and works. Are we saved by faith alone? What about James saying that “faith apart from works is dead” (James 2:26)? Don’t worry — there’s no contradiction here, but we do need to think carefully.
Paul makes it absolutely clear that we are justified — declared righteous before God — by faith alone, apart from works of the law. In Ephesians 2:8–9 he writes: “For by grace you have been saved through faith. And this is not your own doing; it is the gift of God, not a result of works, so that no one may boast.” And in Romans 3:28: “For we hold that one is justified by faith apart from works of the law.” Our standing before God is not earned by what we do; it is received by faith in what Jesus has done. This is the glorious truth of the Gospel — that sinners can be made right with a holy God not through their own efforts but through trusting in Jesus’ finished work on the cross.
But here’s the thing: genuine faith doesn’t stay alone. It produces fruit. It works itself out in obedience and good deeds. This is what James is getting at. He’s not saying we earn salvation by our works; he’s saying that real faith will inevitably show itself in how we live. If someone claims to have faith but there is no evidence of it in their life — no love for God, no obedience to His Word, no care for others — then we have to ask whether that faith is genuine at all. James uses the example of Abraham, who showed his faith by his willingness to offer Isaac (James 2:21–22). His works didn’t earn him righteousness; they demonstrated the reality of the faith he already had.
Think of it this way: we are saved by faith alone, but the faith that saves is never alone. It is always accompanied by repentance, love, and a transformed life. These things don’t save us — Jesus saves us — but they are the evidence that we have truly believed. As Paul says in Galatians 5:6, what counts is “faith working through love.”
The Object of Faith Matters
We must also understand that it’s not the strength of our faith that saves us but the object of our faith. Some people have weak faith, plagued by doubts and fears, and yet they are saved because they are trusting in Jesus. Others may have strong confidence, but if they’re trusting in the wrong thing — their own goodness, their religious rituals, a false god — that faith cannot save them. A person might have tremendous faith that a broken bridge will hold them, but all the faith in the world won’t stop them from falling. What matters is whether the bridge is sound.
Jesus is the solid ground. He is the sure foundation. He is the one who actually saves. Our faith doesn’t earn anything; it simply receives what Jesus has accomplished. Think of faith like an empty hand reaching out to accept a gift. The hand doesn’t deserve the gift or earn it; it simply receives it. That’s what faith does — it receives Jesus and all His benefits. This is why Scripture can speak of us being saved “by” faith (Ephesians 2:8) and also “through” faith (Romans 3:22). Faith is the instrument, the means, the channel through which salvation comes to us. But Jesus Himself is the Saviour.
This is tremendously encouraging for those who feel their faith is weak. You don’t need great faith; you need faith in a great Saviour. Jesus said that even faith as small as a mustard seed can move mountains (Matthew 17:20). What He’s saying is that it’s not the size of your faith that matters but the size of your God. Even a trembling, struggling faith, if it is directed toward Jesus, is saving faith. The father who cried out to Jesus, “I believe; help my unbelief!” (Mark 9:24) — that’s real faith, honest faith, and Jesus honoured it.
Living by Faith
But faith isn’t only for the moment of conversion. The Christian life from start to finish is a life of faith. Paul declared in Galatians 2:20: “I have been crucified with Christ. It is no longer I who live, but Christ who lives in me. And the life I now live in the flesh I live by faith in the Son of God, who loved me and gave himself for me.” We are justified by faith, and we are sanctified by faith, and we will one day be glorified — all through faith in Jesus.
The prophet Habakkuk was given a message that would echo through the centuries: “the righteous shall live by his faith” (Habakkuk 2:4). This verse is quoted three times in the New Testament — in Romans 1:17, Galatians 3:11, and Hebrews 10:38 — showing how central it is to the Christian life. We walk by faith, not by sight (2 Corinthians 5:7). We trust God when circumstances are difficult, when the future is uncertain, when we don’t understand what He’s doing. That’s the daily exercise of faith.
And this kind of faith isn’t something we generate ourselves. Even faith is a gift from God. Ephesians 2:8 tells us that salvation is “the gift of God,” and the grammar suggests that this includes faith itself. We cannot muster up saving faith by our own willpower; the Holy Spirit works in us to bring us to faith. Jesus said, “No one can come to me unless the Father who sent me draws him” (John 6:44). Faith is our response, yes, but it is a response enabled by God’s grace. This protects us from pride — we cannot boast in our faith as if it were our achievement — and it gives us confidence that God, who began this good work, will bring it to completion (Philippians 1:6).
Conclusion
So what is faith? It is trusting in Jesus. It is taking God at His Word. It is resting our whole weight upon the finished work of Jesus on the cross, confident that He is who He says He is and that He will do what He has promised. It is not a blind leap but a response to God’s revelation. It involves knowledge, assent, and personal trust. It is not our works that save us but faith in Jesus, yet genuine faith will always produce a changed life. And the wonderful news is that even weak, struggling faith is enough, because what matters is not the strength of our grip on Jesus but His grip on us.
If you have never come to Jesus in faith, I would urge you to do so today. Recognise that you are a sinner in need of a Saviour. Believe that Jesus, the Son of God, died for your sins and rose again. Trust in Him — not in yourself, not in your good deeds, not in religion — but in Him alone. And if you do know Jesus, keep walking by faith, day by day, trusting Him in every circumstance, looking forward to that day when faith will become sight and we shall see Him face to face.
“For by grace you have been saved through faith. And this is not your own doing; it is the gift of God, not a result of works, so that no one may boast.”Ephesians 2:8–9
Bibliography
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