Why we can have faith — Hebrews 10:19–39

Good morning dear Mosaic Family and guests. 

Imagine standing outside a building, convinced the door is locked. You hesitate—checking if you’re allowed in, wondering if you’ve got the right key, worried you might be turned away. Eventually someone inside calls out, ‘Why are you standing there? The door’s already open.’

Nothing changed about the door. The only thing missing was confidence to walk through it.

The letter to the Hebrews that we’ll be in for the next 3 weeks, suggests that many believers live like this with God—not because the way is closed, but because they’re unsure if it’s really open. In our series on ‘faith’ that we’re starting today, we’ll focus on the last few chapters of the Book of Hebrews, and in these chapters, the writer insists that the door has already been opened, not by our belief or faith, but by Christ Himself.

Hebrews is written to believers under pressure—tired, tempted to drift, and wondering whether following Jesus is really worth it. If you’re anything like me, then you can identify with those challenges as well. The letter responds not by giving techniques, but by unfolding a breathtaking vision of Christ. Chapters 1–9 show that Jesus is greater than angels, Moses, and every priest, and that His once-for-all sacrifice has accomplished what the old covenant, a system that pointed toward holiness but could never finally deal with sin. By the time we reach chapter 10, every barrier has been removed. The question is no longer what Christ has done, but how we now live by faith in response.

Our sermon next week will focus more specifically on what faith IS, the substance of faith, and part 3 will look at what a life of faith looks like in everyday life, but today we’ll focus on why we can have faith, why we can say, the door is unlocked and we’re being asked to come in.

This topic one of the most significant differences about following Jesus—not because Christians are better people, but because the gospel, the good news of Jesus begins in a different place. Every other way of life begins with what we must do to reach God, meaning, or hope. Hebrews says becoming a Christian begins with what God through Jesus has already done. 

And that’s exactly where Hebrews turns in chapter 10. After nine chapters explaining what Jesus has done, the author now addresses us directly. For the first time in the letter, the focus is no longer on Christ’s work for us, but on our response to it. And the very first word matters: “Therefore.” 

Everything that follows rests on what has already been finished. So listen carefully to how the author begins—not with a command to do more, but with a declaration of what is already true.

READ: Heb 10:19-22

1. Faith Is Grounded in What Christ Has Done, Not in What We Believe Hard Enough

You’ll hopefully immediately notice that these verses not only begin with a ‘Therefore’, they include 2 ‘since’s’.

3 very strong words that place the emphasis purely on what Jesus has already done for us. 

When Hebrews says “therefore” and “since,” it is pointing us back to the heart of the good news, the gospel. The Bible’s claim is not that human beings can eventually find the right key to God’s door, but that God Himself has opened the door to us in Jesus. We were stuck outside, separated from God by sin—by our rebellion, our guilt, and our inability to make ourselves clean. No amount of effort, sincerity, or religious activity could unlock that door from the outside.

But Jesus lived the sinless life we could not live, and died the sinners death we deserved to die, and offered Himself as a once-for-all sacrifice for sin. On the cross, the door was opened fully; in the resurrection of Jesus from the dead, it was held open permanently. Nothing remains to be added. Nothing needs to be unlocked ever again.

That is why Hebrews can say, “Since we have confidence… since we have a great priest…” Faith is not what opens the door—faith is trusting that the door really, truly, eternally is open, and stepping through what Jesus has already secured for us.

“Since we have confidence…”

The author assumes that followers of Christ have confidence before any command is given. Faith, therefor, is not the act of creating confidence, by believing really really hard…faith is the act of trusting that confidence has already been given.

It’s an interesting question to consider…’Is my confidence in faith itself?’ (as if faith was a thing) or ‘Is my confidence in Jesus and His complete and final door opening skills?’

This matters hugely, because many believers live as though confidence with God must be earned and sustained by spiritual performance. Hebrews insists the opposite: confidence is grounded in what Jesus has already accomplished. Faith begins when we stop trying to feel worthy and start trusting that we already are welcomed.

“Since we have a great high priest…”

This is where the image comes fully into focus.

Jesus did not simply open the door to God’s presence and walk away. He did not unlock it and leave us to wonder whether we might lose access again. Hebrews tells us that Jesus is the great and final High Priest, which means He now stands in God’s presence on our behalf.

If the cross is the moment the door was opened, the eternal high priesthood of Jesus is the reason it stays open.

Right now, Jesus represents us before the Father. He intercedes for us. He ensures that our access to God is not fragile, temporary, or dependent on our spiritual consistency.

This is deeply good news for tired, doubting, or growing believers.

When we fail, when our faith feels weak, when prayer feels like they’re bouncing off the ceiling or God feels far, the door does not quietly close again—because it is not held open by us. It is held open by Jesus.

Faith rests not on how consistently we come to God, but on the One who consistently brings us before God.

Faith does not create access, faith receives access.

If you’re here today and you’re still exploring Jesus or still working out what you believe — this is important. When the Bible talks about faith here, it’s not talking about becoming religious or getting your life sorted before coming to God. Faith is simply trusting that what God says about Jesus is true, and that the door He has opened is really open for you to come and meet with Jesus.

You don’t need to feel confident. You don’t need to have all the answers. Faith may simply begin with being willing to step toward the door and say, “If this is true, Jesus help me to see it.”

2. Faith Expresses Itself as Drawing Near, Holding Fast, and Staying Together

(Hebrews 10:22–25)

Once the foundation is laid—since we have confidence, since we have a great high priest—Hebrews finally tells us what faith looks like in action.

And notice this carefully: faith is not described as something we have or possess, but something we then put into practice.

The author gives us three encouragements or commands, each beginning with the same phrase: “Let us…”

“Let us draw near…”

Faith begins by drawing near to God.

This is not physical closeness and it is not emotional intensity. It is the deliberate movement of our deepest trust toward God—coming honestly and openly towards Him. Movement away from the idols of our time. Away from money, comfort, power, sexualisation, away from anything as our greatest source of trust, and towards our great saviour who loves us and gave Himself for us.

The writer is explicit:

22 let us draw near to God with a sincere heart and with the full assurance that faith brings, having our hearts sprinkled to cleanse us from a guilty conscience and having our bodies washed with pure water. 

Faith here is not self-confidence—it is confidence in the cleaning work that God does in us. The order is so helpful… first our ‘hearts’ are sprinkled clean from a guilty conscience first…and then our ‘bodies’ are washed clean with pure water.

We do not draw near because we feel clean. We draw near because Jesus has made us clean by dying in our place for our sins and has forgiven them and removed them from us as far as the east is from the west. Our consciences are clean because God has chosen never to remember our sins against us again. Jesus has on the cross, received in our place the punishment and separation for sin that is rightly ours, so that we are set free and can have the same confidence of Gods closeness as Jesus Himself has.

Dear friends, although being close to Jesus changes how we live in our bodies - our character, attitudes and behaviours - and over time, this change comes as a response to Jesus’ grace and closeness, not for it.

I love this image. It explains visually what we’re talking about…

That’s why this is not an invitation to spiritual bravado, but to humble, grateful confidence in Jesus.

Faith says:

“I come as I am, because Christ has already dealt with who I was. He is also at work to make me, in my life and actions, what I already am by faith.”

When we know we are clean and welcomed, we are finally free to stay.

“Let us hold fast…”

Next, faith holds fast, it grips and doesn’t let go.

This language is not about intensity, about how ‘grrrr’ you hold, but consistency.

Not excitement of a moment or experience (as wonderful as those are), but the steady, faithful, commitment over time that just deepens.

Faith holds onto hope not because our circumstances are always good or joyful or stable, but because: “He who promised is faithful.”

The object of faith is doing all the work here.

We are not told to hold fast to our feelings or emotions of faith, or to our certainty, or to the outcomes of things.

We hold fast to hope, because God is faithful. Even when we don’t see immediate results, we refuse to let go of God, because He is faithful. His timing is always perfect, even when it confuses us. His reasons are always just and right, even when we don’t yet understand them. His heart towards all people is always loving and good.

One of the reasons we’re working through Genesis is so that we would learn this—God’s persistent faithfulness toward humanity, the crown of His creation.

The cross is the clearest evidence of Gods faithfulness. As the Apostle Paul reminds us: “He who did not spare His own Son, but gave Him up for us all, how will he not also give us all things in Christ Jesus.”

His faithfulness encourages our faith to hold on to Jesus.

Faith does not cling to certainty—it clings to a faithful God.

“Let us consider how to stir one another up…”

Finally, having shown how Jesus secures our faith, the writer turns outward.

Hebrews assumes something deeply countercultural:
“Faith is not sustained alone.”

We discussed this in depth at our last Foundations evening as well.

To “consider one another” means to:

• To pay deliberate and thoughtful attention to one another. Gifts. Talents. Passions. Calling in God. Needs.

• To provoke love and good works (on my own I’m lazy, waste time, talents and treasures easily)

• To encourage one another regularly (again, if left to my own, I will easily drift. Stop coming to stuff, particularly Sundays and LifeGroup. I get stuck in cycles of sin and shame. Tend to want to hide myself from God and people. We need one another to spur on, to encourage, to remind us of the grace in which we stand and the certainty of our faith because of what Jesus has done)

Faith is strengthened and matured in shared life, not private isolation. Jesus assumes this same principle when He speaks about life together in the church in Matthew 18. Faith is meant to be lived where others can see us, know us, and walk with us. It is deeply tragic that some Christians end up living in this private isolation.

This is why neglecting to meet together is not a scheduling issue—it is a faith issue.

Faith grows as we remind one another of what is true when life makes it hard to remember.

Faith is personal, but it is never private. It grows best when it is shared.

3. Faith Must Continue — Shrinking Back Is the Real Danger

(Reference Hebrews 10:26–39)

At the end of this section which we won’t read in full, the tone shifts—and it’s meant to. Hebrews does not end its call to faith with encouragement alone. It adds a caution, a warning, because faith is not just about stepping through an open door once; it’s about not quietly walking back out again.

And notice the contrast the author draws. It is not strong faith versus weak faith, or confident faith versus doubting faith. It is enduring faith versus shrinking back.

Shrinking back almost never happens in a moment. It happens slowly—through withdrawal, disengagement, and quiet retreat. Not through honest questions or seasons of struggle, but through slowly convincing ourselves that distance is safer than trust.

And here’s the key: the danger is not that the door closes. The danger is that some stop believing it is really open.

That’s why the author can say, “But we are not of those who shrink back and are destroyed, but of those who have faith and (through that trust in Jesus) preserve their souls.”

This is not condemnation—it’s a statement of identity. Remember the graph we looked at? It’s a reminder of who we are. We ARE people who have been welcomed in, and who now live by faith in what Christ Jesus has done.

Faith begins when we realise that Christ has already done everything necessary to open the way to God. The door is not locked. It does not need to be forced. It has been opened by Jesus Himself—and it is held open by His faithful, priestly work.

That’s why faith is not a force we direct at things or situations or a confidence we manufacture. Faith is trusting that the door really is open, drawing near because we are welcomed, holding fast because God is faithful, and staying together because we were never meant to walk through this life alone, and we enjoy it more and are better for it.

And when life becomes hard, when doubts creep in and our strength feels like its fading, the answer is never walking away from the door — but faith is about staying close to the One who opened it. Again and again we see that, faith is our response to a faithful God who loves us and who has already made the way.

Amen