Passage: Exodus 20:18-26

The Big Idea

After the Ten Commandments, the people trembled and stood far away. The law is holy, but it isn’t good news; it shows us our guilt, and it drives us back. They begged for a mediator, and God promised a Prophet like Moses: Jesus, the one Mediator between God and man. Then, immediately after the law, God gave instructions for an altar: plain earth or uncut stone, no tools, no steps. We can’t build our way up to God. We come to His altar empty-handed, and He comes down to us. Exodus 20 isn’t just about law; it’s about grace.

The Problem the Law Creates

Take a deep breath. We’ve finished the Ten Commandments, the perfect list of rules God gave His people. They show what God is like and what He loves. They show what perfection looks like: what Perfection would do if He were born in Bethlehem centuries later.

Hardly anyone argues that they’re wrong. Nearly everyone agrees with them.

But they create a huge problem. Now we know how selfish, evil and wrong we are. The light has flashed on us, and there’s nowhere to hide. “I didn’t know” is no longer an excuse. Now everyone knows, and everyone is guilty.

The law has measured each of us and found us far too short. Not just a little short. Our lives stand in opposition to it. Even if we agree with it and try our best, in the end we fall short, and if we break one law, we’re lawbreakers (James 2:10).

The law is not good news. God’s holy standard isn’t wrong, but it isn’t good news. It’s serious business with serious penalties.

The Ten Commandments were never given to save people, but to show them their need for a Savior (Galatians 3:24).

Standing Far Off (Exodus 20:18-19)

All the people witnessed the thunder and lightning, heard the trumpet and saw the mountain smoking, and they trembled and stood at a distance.

What do you do when you hear bad news? Tremble and back away.
A movie director would be impressed with how God set the scene: thunder, lightning flashes, a trumpet blast, a mountain wreathed in fire and smoke. “Don’t do this!” Boom! “Don’t do that!” Fire!
God’s holiness, glory and power were on full display.
And it made them back up. It didn’t draw them near.
There’s nothing inviting about the law. It’s like saying, “Let’s try to fit you into a box you’ll never fit in.”

“But don’t we use the law when we talk to unbelievers, or to believers living in disobedience?” Yes. But we have to use it rightly. It’s never the solution. It helps people see they need a solution, a Savior: Jesus.

And it worked. Look at the people’s response.

They said to Moses, “You speak to us, and we’ll listen. But don’t let God speak to us, or we’ll die.”

They saw they couldn’t measure up. They weren’t good enough.
They saw their need for a mediator, and they wanted Moses to be it.
What’s a mediator? Someone who speaks to the people for God and to God for the people. A go-between, a translator, a servant both ways.

They felt shame and fear, and thought they might die. That’s how many people feel in church, because for them church is about the law, measuring up to a perfect standard, instead of what it’s truly about: the Mediator.

The Promised Mediator

Their request for a mediator might look ignored here. But God’s grace is sometimes hidden from those who don’t look deep enough. God’s Word is a treasure chest of grace.

Moses later retold this moment: the Lord said, “What they’ve said is good. I will raise up for them a Prophet like you from among their brothers, and I will put My words in His mouth, and He will tell them everything I command Him” (Deuteronomy 18:17-18).

What a promise!
God allowed Moses to serve as Israel’s mediator, but He promised another Prophet, one who would be the perfect Mediator.
Who is that perfect Mediator? Jesus (Acts 3:20-22).

“For there is one God and one mediator between God and men, the man Christ Jesus” (1 Timothy 2:5).

Fully God and fully man.
He can represent each to the other. He brings peace and restores relationship.
What a wonderful Mediator Jesus is!

First the Law, Then the Altar (Exodus 20:20-21)

So far: God gave the Ten Commandments, and the people were driven away by their awareness of failure.

But God made provision for their failure: an altar. It’s the very next thing He talks about.

The law, then the altar!

Moses told the people, “Don’t be afraid. God has come to test you, so that the fear of Him will be with you to keep you from sinning.”

The test revealed their weakness, and their need for God’s grace, help and rescue.

The people stayed at a distance, but Moses approached the thick darkness where God was.

Moses was a murderer! How could someone like him draw near to God?
Because he knew and trusted God’s grace. He came by faith.
“But now in Christ Jesus you who once were far off have been brought near by the blood of Christ” (Ephesians 2:13).

No Gods of Silver or Gold (Exodus 20:22-23)

The Lord told Moses to tell Israel: “You’ve seen for yourselves that I’ve spoken to you from heaven. Don’t make any gods of silver or gold to set alongside Me.”

“I’m kind of a big deal.”
“Don’t shrink Me. Don’t explain away My standards.”
“I am great and holy, and you can’t remake Me out of silver and gold into a god you’d be more comfortable with.”

So what do we do? We “alter” our view, by coming to the altar.

An Altar of Earth (Exodus 20:24)

“Make an altar of earth for Me, and sacrifice on it your burnt offerings and peace offerings, your sheep and cattle. Wherever I cause My name to be remembered, I will come to you and bless you.“

The Hebrew word for altar, mizbeach, comes from a word meaning “to slaughter.” It’s a place of sacrifice.
What happened if they didn’t keep the law? Death.
What happened at the altar? Death.
Interesting. Do you think those two things are connected?
Under the law, blessing came only if you kept the entire law. So God gave another way to be blessed and live with Him: on the basis of sacrifice.
The death of a lamb or ox provided for their failures.
And it pointed ahead to the Lamb of God, who would die for the sins of the world.
“I will come to you and bless you.” At the altar, God comes to them.

No Tools (Exodus 20:25)

“If you make Me an altar of stones, don’t build it with cut stones, for if you use a tool on it, you will defile it.”

The altar wasn’t to be improved by human craftsmanship. No tools. No effort to make it look better. Not fancy. Not man-made.

Paul says God chose the foolish things of the world to shame the wise, the weak to shame the strong, the lowly and despised and the things that are nothing, so that no one may boast before Him. And because of Him you are in Christ Jesus, who became for us wisdom from God, righteousness, holiness and redemption, so that, as Scripture says, “Let the one who boasts boast in the Lord” (1 Corinthians 1:27-31).

You can’t build your own altar. You can only come to His.
If anything depended on us, our flesh could boast before Him.
But God must receive all the glory, so this can’t be how we relate to Him: by our own strength, ability, effort or sincerity.
There’s another way: we can be in Christ, and He becomes everything we need.
So the Lord Jesus is glorified, not us.
That’s why the gospel works, and why it’s so free. It gives Jesus the glory of forgiving and transforming us by grace. We do God’s will by believing the gospel and coming to the altar.
God’s mercy and grace are given at the altar, not through the law.
The great altar is Calvary: a hill of rock and earth where the Lamb of God was slain.

Paul says God saved us not because of any righteous things we did, but because of His mercy, through the washing of new birth and renewal by the Holy Spirit (Titus 3:5).

Our works don’t earn God’s favor.
As Arthur Pink put it in essence, a sinner can’t approach the thrice-holy God with anything his own hands have produced.

Remember Cain and Abel? Cain brought the fruit of his own labor from the cursed ground. Abel brought a lamb, a blood sacrifice, by faith. God accepted Abel’s offering and not Cain’s (Genesis 4:3-5; Hebrews 11:4).

God rejects self-effort. He calls sinners to come to Him empty-handed and humbly ask for mercy we don’t deserve, and He promises to give it: grace and love, as free and limitless as the air we breathe.

No Steps (Exodus 20:26)

“And don’t go up to My altar by steps, so your nakedness won’t be exposed on it.”

No stairs. Instead of demanding that we climb up to Him, He comes down to us. Every detail fits grace.

Arthur Pink pointed to Philippians 2, where Christ descends: though He was in the form of God, (1) He made Himself of no reputation, (2) took the form of a servant, (3) was made in the likeness of men, (4) humbled Himself, and (5) became obedient to death, even death on a cross (Philippians 2:6-8). Pink noted these five downward “steps,” five being often associated with grace. The steps are all His, going down. There are no steps for us to climb up.

What about the nakedness?

Later, God required the priests to wear linen undergarments when they ministered at the altar (Exodus 28:42-43; Ezekiel 44:18). (So now you know where underwear came from!)

God doesn’t want to see flesh. In Scripture, the flesh often pictures human effort.
This applied to the priests, because they modeled for the people how to approach God.
Any attempt to climb up to God by our own effort only exposes our shame more.

Remember Adam and Eve. After they sinned, they realized they were naked and sewed fig leaves together. But what good were fig leaves when God sees everything? When they heard God walking in the garden, they hid. Why hide, if their nakedness was covered? Because fig leaves can’t cover shame before God. (They fig-ured out the idea of underwear, but they had no idea how to make it work.)

They didn’t have an altar. But God did something remarkable: He made garments of skin and clothed them (Genesis 3:21). Something died so their shame could be covered.

In Eden before sin, no altar was needed. Adam and Eve were innocent. They had no shame. They could walk with God freely, and God delighted in their fellowship.
Sin made the altar necessary.
God didn’t owe us an altar. But because He loves us, He graciously provided one.
In the law, God revealed His righteousness. In the altar, He revealed His mercy and grace.

What Does It All Mean?

There’s no display of human flesh at God’s altar.

We bring nothing. He provides everything out of His love and mercy. That’s called grace.

Some think Exodus 20 is all about law, the Ten Commandments. But really, it ends with God’s grace: His sacrifice and His mercy.

Grace Takeaway

May we all hear the law. May we all be broken by its demands, and stop trying to climb steps we were never meant to climb. And may we all come to the altar, where God comes down to meet us, and be forgiven, restored and given life through the death and sacrifice of Jesus, our one Mediator.

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An Altar-ed Mindset