Hebrews 3:1-4:13

What does it mean to be a christian? what is a christian? 


the beginning of v14 tells us what a christian is. A christian is someone who has come to share in Christ 

That is, something has happened to a Christian so that now they belong to Jesus. In a very real sense they have become a part of Jesus.  They share in Him. 

Martin Luther said that the best illustration of the relationship that a christian has with Jesus Christ is that of marriage. In marriage you come to be ONE FLESH with another human being.  And you belong to each other.  And perhaps you then have the same name, perhaps the same bank account, hopefully the same home, the same future – you are caught up in each other.  A Christian has come to share in Christ by trusting Him with their life and death and eternity.  And now through trusting Jesus we belong to Him and He belongs to us.  So His name and status is ours – we are declared to be righteous children of God.  His future is also ours – He will not divorce us, we are in an indissoluble union with Jesus and where He is, we will be also.  He has gotten through death and lives immortally, we will get through death and live immortally with Him.

So that’s what a Christian is – someone who has come to share in Christ.


Now, How do you know that you are a Christian? 

What evidence is needed? Profound experiences of God? would be great but their presence or absence doesn’t prove anything. Moral goodness? again, that would be great but again its presence or absence doesn’t prove you’re a christian. What about church involvement? can i rest on that? No. 

Look at the end of v14 We have come to share in Christ, if indeed we hold our original conviction firmly to the very end. 

The way you know that you’re a christian is that you persevere in your belief in Jesus to the end of your life. 

This isn’t meant to rock our assurance. In fact quite the opposite. it’s telling us that the way you know that you’re a Christian is that today you’re a believer. Do you believe Jesus is God, your saviour? If so then you are a Christian. Now, persevere in your belief to the end of your life.

One of the major concerns of the letter to the Hebrews is that we stand firm in confidence to the end. This perseverence doesn’t make you a Christian. Sharing in Christ makes you a Christian. But, by the grace of God, true Christians persevere. 

That’s what this letter says to us again and again and in chapters 3 and 4 Hebrews takes us back to the Old Testament to urge us on to persevere with a warning and a promise. 


It all revolves around the quote from the book of Psalms in 3:7-11. It’s a direct quote from Psalm 95 a psalm of Israel’s greatest King, David, that speaks about the very first generation of Israelites who were rescued: FROM slavery in Egypt FOR rest in a promised land but who FAILED to make it there. They FELL in the wilderness because they didn’t persevere in their belief

Here’s what the Psalmist wrote v7, 

‘Today, if you hear his voice,

8    do not harden your hearts

as you did in the rebellion,

during the time of testing in the wilderness,

9 where your ancestors tested and tried me

   though for forty years they saw what I did.

10 That is why I was angry with that generation;

I said, “Their hearts are always going astray

    and they have not known my ways.”

11 So I declared on oath in my anger

“They shall never enter my rest.”’


That generation rebelled, they grieved God, and they were not permitted to enter the promised land. It was a great tragedy. 

But here’s what’s important. This is not just distant history. Those things happened then as a warning and encouragement to us. As a foreshadowing of our journey of salvation. 

They were rescued from slavery in Egypt - we have been rescued from the slavery of sin and death.  

They journeyed in the wilderness of Sinai - we journey through the wilderness of this present age

They were headed for the promised land of Canaan - we are heading for the true land of promise of which Canaan was only a foreshadow. We are looking forward to sharing in God’s Divine Rest - the New Creation. 

So these things happened to them as a warning and encouragement to us to persevere 

As the Holy Spirit SAYS 3v7 TODAY if you hear his voice, do not harden your heart as you did in the rebellion. 

So what can we learn from that generation about the nature of sin? what it does to us, what it does to God? What’s the warning here? 


let’s think first about what our sin does to God..

that word anger there in the quote is very important. very important that we understand it rightly.  

because we often think of God as an angry deity. he’s angry with us and we quite frankly are angry with him. his anger means that we can keep him at arms length. 

But if we think like this we are gravely mistaken and have got God completely wrong. 

The anger that is spoken of here is a deep grieving kind of anger. It is the grief of unrequited love. It is the deep pain and hurt of a father with an unruly, rebellious child. It is the right and searing jealousy of a husband with an unfaithful wife. For God is a father and a husband to his people.

In Exodus 19 on the top of Mount Sinai God draughts the 10 commandments with Moses and he says to him. “This is what you are to tell the people of Israel: You yourselves have seen what I did to Egypt and how I carried you on eagles wings and brought you to myself. Now if you obey me fully and keep my covenant, then out of all nations you will be my treasured possession.”

Israel had seen what God had done to the superpower Egypt, the ten plagues, the escape through the red sea, he had led them by a pillar of fire at night and of cloud during the day. God had carried them to himself and now as the covenant promises are drawn up this is like their wedding night. And Moses carries the tablets of the ten commandments down the mountain and as he approaches the Israelite camp he finds that they are worshipping other gods. 

For 40 years God leads Israel, his wife, in the wilderness. Seeking to teach her to trust him. v8 calls it the time of testing. So sometimes God delayed the things his people needed - food or water - to train his people to trust him - to pray, to wait. If you’ve been a Christian any time, you’ll know God does this. But rather than wait the people became angry and complained and spoke against God again and again. they tested and tried him. 

And when God finally brought them to the borders of the promised land. And spies went in and returned and said - yes there are enemies there but it’s a land flowing with milk and honey and God has promised it to us - the people said no. we’re not going in. take us back to egypt. 


In Hosea chapter 11 God says this:

“When Israel was a child, I loved him, and out of Egypt I called my son. 2 But the more I called Israel, the further they went from me.  They sacrificed to the Baals and they burned incense to images. 3 It was I who taught Ephraim to walk, taking them by the arms; but they did not realise it was I who healed them. 4 I led them with cords of human kindness, with ties of love; I lifted the yoke from their neck and bent down to feed them…. 7 [But] My people are determined to turn from me.  (Hosea 11:1-7)

The book of Hosea is all about the adultery of the people of God. God consistently doing whatever it takes. paying whatever cost to get his wife back. But she cheats on him again. And he cries out with grief and pain. 

I don’t know what picture of God you have.  I don’t know what picture of your sins you have.  I think we tend to view our sins as legal transgressions against some impersonal rule-book.  No the LORD Jesus is our Husband.  And He is grieved – not so much by this particular sin or that – but by our hearts that seem to pursue satisfaction in anything but Him.  He is the spurned Lover, the rightfully Jealous Husband to whom we belong but against whom we sin every day.

Against you and you alone have I sinned, Oh God 

Oh people do you feel it?

God so loves us - he wants us for himself.. We hurt him. We hurt him. 

On the borders of the promised land. they say. Nope, We’re not going in. No thank you. Let’s find someone to take us back to Egypt. And finally..finally God gave them what they wanted. ‘They shall never enter my rest.’  It pains him with grief we are the apple of his eye but God gives us what we want. He never hands us over to what we don’t want.  He always hands us over to what we do want.


What is wrong with us?! What is wrong with us?

Well, The whole passage screams to us – it’s the heart, the heart, The heart of our problem is the problem of our heart.

Look at verse 8 – do not harden your hearts

Verse 10 – their hearts are always going astray

Verse 12 – See to it, brothers and sisters, that none of you has a sinful, unbelieving heart

Verse 15 – do not harden your hearts

The LORD Jesus is the great heavenly Husband and He’s not primarily after our wills, He’s not primarily after our intellect – He’s after our hearts. But by nature our hearts are hard, wandering and unbelieving.  And at the end of v13 we see that they can get even worse through sin’s deceitfulness.  Sin lies to us.  We are dying of thirst in the desert and instead of going to our Lord Jesus and asking for the living waters of His Spirit – sin comes along and says “Here, try this bucket of salt.  It’s much tastier than boring water.  This is what will satisfy you.”  So we spurn our Lord and His Living Waters and we slake our thirst on a bucket of salt.

And as we believe the deceitfulness of sin – it hardens us. It makes us less and less likely to ask for the Living Waters in future.  That’s the scary thing.  Sin doesn’t change the LORD’s attitude to us so much as it changes our attitude to Him.  Sin doesn’t harden Jesus’ heart towards you, sin harden’s your heart towards Jesus. Like the skin that forms on the top of paint our hearts seal over, our consciences lose sensitivity, we become comfortably numb.


What can be done to enable us to persevere? To change our hearts. Well there is hope. 

God can do things with hard hearts 

First there is his word 

We’re told in chapter 4:12 that the Word of God can come like a surgeon’s scalpel and bring out the thoughts and attitudes of our hearts. It doesn’t sound like a lot of fun does it, heart surgery isn’t fun – but it’s necessary.  And when we read or hear the Word of God it can expose what our hearts are like. I hope that’s even happening now. Some of the caloused scar tissue is cut away. the living and active word of God jump starts our dead cold hearts to life again. How much we need God’s word as a daily spiritual defribulator. 


then there’s God’s people 

Read with me from v12:

12 See to it, brothers and sisters, that none of you has a sinful, unbelieving heart that turns away from the living God. 13 But encourage one another daily, as long as it is called Today, so that none of you may be hardened by sin’s deceitfulness.

Every day. It only takes 24 hours for our hearts to be hardening. We are responsible for one another. We need one another.  

Proverbs 20v5 says The purposes of a man’s heart are deep waters, but a person of understanding draws them out. If you know Jesus, you are a person of understanding.  Jesus is Wisdom (according to Proverbs) and if you have Jesus you have understanding.  That means that if you know Jesus and if you get to know me – there’s a deep sense in which you know me better than I know myself.  I am a mystery to myself – I look down at my heart and it’s deep waters, I can’t see the bottom.  My heart is deceitful and wayward and difficult to pin down.  But you are much better positioned to diagnose the problems in my heart than I am. And i’m much better positioned to diagnose yours than you are. We don’t know ourselves – we need community to draw out what’s really going on in us so we can deal with these wayward hearts of ours. We’re talking here about the kind of community that gets to the heart – are you pursuing that kind of encouragement?  We won’t survive the wilderness without it.

Dietrich Bonhoeffer wrote a wonderful little book on the importance of encouragement and he called it “Life Together.”  And a line from that book is one of the most insightful things I’ve ever heard about encouragement.He said: “The Christ in the word of my brother is stronger than the Christ of my heart.” By which He means, I might know in my head that Jesus is my Glorious and Beautiful Husband who shed His own heart’s blood for me, but when my Christian brother or sister looks me in the eye and says “Giles, Jesus loves you and gave Himself for you.”  That has a power to soften the hardest heart. because faith always comes to us from a word outside ourselves not from within. when we meet together we have the power to offer Christ to one another in ways that keep our hearts soft and trusting.


God’s word, God’s people, 

finally God’s promise

4v1 .. the promise of entering God’s rest still stands,

4v9 There remains, then, a Sabbath-rest for the people of God.

Whenever we talk to each other and ask each other how we are. whether we’re doing quite badly or quite well we’re always tired. ‘I’m ok, i’m just tired. i need a holiday’ You know, deep in the human condition we all need a good rest. We long for rest. And God has promised us a share, in Christ, in his eternal rest. God promises it with all his heart. A future, permanent place of rest. He wants us to enter in. 

4v3 we who have believed enter that rest - it’s ours.  

And so let us persevere in believing every day of our lives - until we finally come home to him, to the lover of our very souls. 

since the promise of entering God’s rest still stands, 4v1 let us be careful that none of you be found to have fallen short of it.

Let us, therefore, 4v11 make every effort to enter that rest, so that no one will perish by following their example of disobedience.

let’s pray