Being a prophet was one of the hardest jobs in the Old Testament. A prophet had to speak unsettling words, confronting sinners with sin and warning of judgment. They were usually unpopular, often persecuted. So a prophet needed a really clear sense that this is what he was called to do, the conviction that because God commanded, he simply had to speak—no matter what.
The prophet Isaiah had a firm grip on his mission. There was no doubt, even as he ministered for four decades, that the holy God had called him. And for his ministry, there was no more important moment than what took place in Isaiah 6. This encounter shaped him and his message for the rest of his life.
It happens at what was a turning point for Judah. We’re told that it was “the year that King Uzziah died” (6:1). The year is 740 BC, and Uzziah has been on the throne in Jerusalem for 52 long years. He wasn’t always a great king, but Chronicles tells us that when he did seek the LORD, he was blessed. When a king prospered, the land prospered too. So things were pretty good in Judah right now: making money, buying land, enjoying the finer things.
A long-reigning king means stability. But what happens when a king dies? Fifty years of steadiness suddenly evaporate, and there is uncertainty. Now what? Especially when you see what’s happening among the nations. The Assyrians were on the rise, a violent and powerful empire, and it looked like none could stand against their aggression. Uzziah had been a seasoned king, clever in the ways of the nations. Now he was dead. Who could step into the gap?
The strong and smart and influential people of this world are but a breath. The president with absolute powers and nuclear weapons today could be gone by tomorrow. The lovable prime minister might be out by the end of the year. It’s foolish to put our trust in any human. They won’t save and they can’t protect.
So the first words announce what should be a crisis, from our point of view. The king is dead. An invasion looms. The world is totally messed up. But then Isaiah gets to see with startling clarity: the King is on his throne. He never went away, and He never will! He is the holy Lord, the God who reigns, who cleanses, who judges, and who saves. This is our theme,
The holy Lord calls Isaiah as His prophet:
1) the stunning revelation of God’s glory
2) the swift removal of Isaiah’s uncleanness
3) the surprising result of Judah’s unbelief
1) the stunning revelation of God’s glory: In this moment of crisis, Isaiah is allowed to see the one sure answer to every anxiety and fear: the Lord God. “I saw the Lord” (v 1), he says. Isaiah is having a vision. Scripture says that no one can see the Lord, for God is spirit, invisible and dwelling in unapproachable light. Yet this is still very real for the prophet, and it’s something God does more than once: He shows himself in some kind of form so that it will be a comfort for his people. Think of how He appeared to Abraham, to Moses, or to Elijah.
Isaiah ‘sees’ God, yet makes no effort to describe God. He mentions his throne, his robes, his heavenly servants, but it’s as if he dares not lift his eyes any further. He hesitates to look fully upon God, for he has already seen enough.
For there is the Lord, “sitting on a throne, high and lifted up, and the train of His robe filled the temple” (v 1). It really is the picture of a king. First, his name, ‘the Lord,’ not the familiar covenant name Yahweh, but the Lord as ‘Adonai,’ the sovereign one, free to do what He pleases. Second, see his position on a throne, the seat of authority, from where He commands nations and judges sinners. Third, his throne is “high and lifted up,” for God is beyond anyone’s ability to control or knock down. Looking up to this God, you have to be reminded that you are lesser, smaller, weaker.
Now, when we have dreams, they don’t usually make a lot of sense. Very different images and ideas and people are all blended together, and in the morning we struggle to put it into words. That’s kind of what’s happening to Isaiah. Not only does he see the Lord on a high throne, but his throne is in the temple, and somehow his robes are filling the temple.
Was this the Jerusalem temple, or perhaps some other temple, a heavenly one? We don’t know. At any rate, the temple marked the reality of God’s presence in his people’s life. God was near, and you could draw near.
Yet He is so grand and glorious that his royal robes prevent you from entering. Kings always like to wear fancy garments, long flowing robes that impress and that tell a history of power and conquest. But this was no ordinary robe, for it is overwhelming in size. It’s as if God’s majesty as king comes spilling out of the temple.
Every king or queen has attendants waiting around them, and so does the Lord, “Above [the throne] stood seraphim; each one had six wings: with two he covered his face, with two he covered his feet, and with two he flew” (v 2). The name seraphim literally means ‘burning ones.’ They are heavenly beings with fiery appearance, who wait on their master.
These seraphim around God are in continuous motion. They are flying, while at the same time covering themselves, and lifting up their voice in endless song. With two wings they cover their eyes, lest they gaze upon God’s glory. They also cover their feet, perhaps because feet are the instrument of life’s direction—the seraphim show that they reject any idea of choosing their own way but will go only where God commands.
And they are singing, like a choir in different parts, ‘crying out to another’ with call and response. This song of praise is brief, yet thunderous, like nothing else in all of Scripture: “Holy, holy, holy is the LORD of hosts; the whole earth is full of His glory!” (v 3).
If we want to emphasize something, we put it in ALL CAPS, or we bold and underline. Or we repeat ourselves to make a point, “I love love this book.” In the Bible, God also makes a point by repetition, like later in Isaiah, “Comfort, comfort my people” (40:1). This makes clear the greatness of God’s comfort—He really means it. But out of all Scripture, only here do we find a three-fold repetition: ‘Holy, holy, holy.’ Words fail to express his glory.
The holy God on his throne is unlike any other, set apart from all things, incomparable in greatness. He is absolutely unique, distinct and transcendent. When we see something really impressive, we often try compare it with something we’ve seen before: “It’s like this, but way better—like something from a movie, but real.” But the glory of God is beyond anything that we can know.
He is holy. And when we say holy, that’s not just one attribute among many. God’s holiness describes all his perfections as God. In every way, in all that He does, He is set apart. His love is holy, his mercy is holy, his truth is holy. In no aspect of God does He fall short or change; in no characteristic is he on our level. Set apart from sin, and beyond all human measure.
Who is holy? ‘The LORD of hosts.’ That’s a familiar phrase, but have you ever pondered what the ‘hosts’ are? A host is a big crowd; in Scripture, God is sometimes said to be the Lord of human armies, like the armies of Israel. And He is Lord of the celestial bodies, like sun, moon and stars. He is also Lord of heavenly creatures. The prophet Michaiah (in 1 Kings) described this scene in heaven: “I saw the LORD sitting on his throne with all the host of heaven around him” (22:19). That general idea fits with what Isaiah has seen so far: being ‘LORD of hosts’ means that God is sovereign over all powers in the universe, visible and invisible—the King.
The LORD is holy, “and the whole earth is full of his glory.” Like his robe fills the temple, so his holiness fills all creation. Everywhere we look, Romans says, we see the majesty of God, the evidence of his rule and power.
This is why the seraphim sing. Standing in the presence of the LORD of hosts, the only fitting response is to revere him, serve him, praise him forever. So in Revelation 4, we hear that his creatures are still singing: “They do not rest day or night, saying, ‘Holy, holy, holy, Lord God Almighty’” (Rev 4:8). Maybe this is the reason that many young children love to sing ‘Holy, Holy’ (in Hymn 5). Not just because it’s a good tune, but because even a child knows that it is just right: God is ‘holy, holy, holy’ and we want to sing to him.
When God reveals his greatness, even the earth itself must react. Think of what happened at Mount Sinai: the whole mountain trembled and quaked and was covered in darkness. Here too, Isaiah sees the temple shuddering in response to the LORD’s glory, “The posts of the door were shaken by the voice of him who cried out, and the house was filled with smoke” (v 4). Picture Isaiah standing outside the temple: the doors to the temple are rattling on their hinges, thick smoke is pouring out—and even if he wanted to, he could go no further. He has come face to face with the LORD of hosts, the great King.
2) the swift removal of Isaiah’s uncleanness: There is a quotation from A.W. Tozer that I love to ponder from time to time: “What comes into our minds when we think about God is the most important thing about us.” For our lives, there’s nothing more pressing, nothing more telling, than our answer to God’s high majesty—to God’s earthshattering reality, the fact that God is, and that He is holy. Does this move you? Does it encourage you? Does it humble you?
Consider Isaiah’s first reaction to the LORD’s holiness: it is sheer terror. He cries in verse 5, “Woe is me, for I am undone!” Utterly ruined. The Hebrew word for ‘undone’ is hard to translate, but it means something like ‘totally silenced.’ There are moments when there’s nothing we can say; it’s the kind of silence which falls on people in face of great disaster or tragic death. Meeting God, Isaiah can’t say anything. He knows he ought to be wiped out.
He gives two reasons for abject humility: he is unclean, and he has seen the Lord. We’ll just focus on that first reason. He says, “I am undone! Because I am a man of unclean lips” (v 5). In an instant he has become intensely aware of his sinfulness.
‘A man of unclean lips.’ The word ‘unclean’ describes much more than outward filth, like a person in serious need of a shower. In Scripture, it’s a special word for everything that is unfit to be in God’s presence. It is moral corruption—and next to the holy God, it is absolutely unacceptable. Maybe we get a faint picture of this when we’ve cleaned the house really well on a Saturday: every surface sparkles, the carpet still has the vacuum cleaner lines on it. And then someone comes in and drops dirty soccer shoes on the carpet or puts a moldy lunch bag on the counter. In the presence of such cleanliness, it’s just wrong to be dirty! That’s what Isaiah feels.
Notice how Isaiah singles out his lips as being unclean. Surely his entire life was unclean, what he did with his hands, his feet, his mind. Isaiah might be thinking about the song of praise offered by the seraphim—that’s exactly what Isaiah cannot do. He isn’t holy like that, so he dare not sing in God’s presence, but must put his over his mouth like Job.
And of course, it’s our words that express what’s in the heart. “From the overflow of the heart, the mouth speaks.” The mouth is a big fat release valve on what’s inside us. What comes gushing out is so often unclean: falsehood, impatience, unkindness, pride. To know a person’s sin, listen to what they say.
Hear how Isaiah speaks for the whole people, “And I dwell in the midst of a people of unclean lips” (v 4). In previous chapters, Isaiah has exposed their sin, their injustice, idolatry, hypocrisy. But now Isaiah acknowledges that he is unclean, right along with them. In God’s holy presence, degrees of sin become irrelevant. Sometimes we feel better about ourselves in comparison to others who are worse sinners. But the holiness of God reveals our true condition: we are all ruined, to the core.
It’s a deeply uncomfortable encounter, but it’s necessary. Necessary for us all, to feel it in our gut, that our sinning makes us unclean. I don’t just mean those times when we feel dirty after sinning—sinning always makes us dirty. How do I dare approach God in prayer, in worship? My pride is unacceptable to him, and my greed, my lack of faith, my envy and gossip.
In the presence of the blazing fire of God’s glory, we’re like the dried yellow grass of summer: just fuel for fire, ready to be burned up in an instant. We’re an unclean people, trembling before a holy God. That’s a dangerous place to be—even fatal. If we sin, and we’re not cleansed, we will die.
But there is a beautiful gospel in Isaiah 6. No sooner has Isaiah confessed, than God acts to remove his uncleanness. That’s the astonishing miracle: the holy God comes near to purify and restore sinners for himself. “Then one of the seraphim flew to me, having in his hand a live coal which he had taken with the tongs from the altar” (v 6).
Mentioning the altar reminds us that this vision takes place in the temple, where there were two altars. One was the incense altar, just in front of the veil; there the priests would put incense onto the coals to send up a pleasing smell to God. The other altar was much larger, situated in the inner court, on which animal sacrifices were offered.
We don’t know which altar the coal comes from, but it doesn’t matter. The fact that there is an altar speaks of God’s grace. By the altar and what happened on it, God dealt with the sins of his people. By blood and fire and sacrifice they could be forgiven through the LORD’s mercy!
The angel takes the coal, touches him, and he says to Isaiah, “Your iniquity is taken away, and your sin purged” (v 7). Through atonement, the sinner is cleansed. A sinner may draw near when the price is paid, the price required by God’s holy justice. And in an act of sheer grace, Isaiah’s sin is removed, not just his sins of lip, but the whole reality of a sinful nature.
Grace is given to Isaiah, just one man in Judah. But the same grace is available to all. Remember what God said to his people in chapter 1, “Though your sins are like scarlet, they shall be white as snow” (1:18). The holy God wants his sinful people to know this: ‘You are a people of unclean lips and hands and minds. You cannot stand before me. But when you know me to be holy, and when you come with fear and trembling—confessing your sins, turning from wickedness—in Jesus’s name, I will make you whole.’
That’s the message God has for his covenant people. He wants them to know it, so He seeks a messenger: “Whom shall I send, and who will go for us?” (v 8). God invites a volunteer, rather than commands one. And like we said, being a prophet wasn’t a job anyone would sign up for. But God has prepared the way. This experience makes Isaiah eager to serve: “Here am I! Send me.” Even before he knows what God will command, he steps forward.
Isn’t that the readiness of true faith? This is the thankful impulse that lives in every thankful believer: ‘I was dead guilty, but I have been shown amazing grace in Christ, so let me serve God in gratitude!’ It’s one of the sure ways you can tell if you’ve been moved by the glory of the Lord. Do you want to serve God? Is it your heart’s desire to give Christ everything? It’s when you, in all your weakness, still put up your hand and say, ‘Here I am! Send me!’
For Isaiah, being a prophet will be intensely hard: forty years of thankless work. But he is motivated! Throughout his ministry, he keeps coming back to the holy God, ‘the holy one of Israel.’ For this vision made its mark. He probably never lost that crushing sense of his own sinfulness, yet with it, the assurance that the holy God forgives sin and gives strength for service.
And that’s what the reality of God does: it transforms! Not just for Isaiah the prophet, but for you the student, and for you the mother, and for you the deacon, the teacher, the grandparent, the neighbour, the husband: the greatness and holiness and goodness and sovereignty of God changes our life. For He forgives us, and He renews us, calls us trust him, and calls us to serve him. And when you know that this holy God is behind you, above you, beside you, within you—you can do anything, anything that He commands.
3) the surprising result of Judah’s unbelief: I said that Isaiah had a tough assignment. God will give him lots of gospel to announce, but also lots of judgment. And the immediate response of God’s people will be unbelief. They will harden their hearts and remain headed for destruction. The doom mentioned in earlier chapters is all but certain.
The latter part of chapter 6 is actually a very strange message to give to a prophet: ‘Tell the people not to listen, not to understand.’ Like a minister coming to a new congregation and saying in his first sermon, ‘I’m going to preach to you for the next ten years, but I don’t expect you to really care. In fact, most of you will tune me out until it’s too late.’ This is God’s word for Judah: “Keep on hearing, but do not understand; keep on seeing, but do not perceive” (v 9).
It sounds wrong, but this is how the Word of God so often works. It opens and it closes; it produces faith and it also confirms unbelief. Point is, there is always a reaction to the Word of God. And in Judah, Isaiah’s message will only solidify their rejection. Because when a person resists the truth, you have to tell the truth again, more clearly. But sometimes just hearing it again can lead to a hardening, ‘No, I don’t want to listen!’ In the New Testament, Jesus and the apostles often applied these verses to the Jews who refused the gospel message.
Judah will persist in their sin: dull hearts, heavy ears, closed eyes. And the result will be exile and destruction. We don’t have time to look at everything Isaiah says about the coming doom: the cities will be laid waste, the houses without inhabitants, the land desolate.
Isaiah will preach until the whole nation is like a field of burned stumps. But then, as is typical of Isaiah, there’s a glimmer of light in the darkness. The land and people are compared to a tree which is cut down, just a stump remaining in a desolate forest. But green shoots appear! There is life in it still! Verse 13: “But yet a tenth will be in it…as a terebinth tree or as an oak, whose stump remains when it is cut down. So the holy seed shall be its stump.” It will be small, the most unlikely of beginnings, but there will surely be regrowth and revival.
Though God’s holy judgment comes against sin, his wrath will not wipe out sinners forever. From the stump of Judah will come a holy seed—a remnant. And from that seed, a Saviour: the root of Jesse, the branch of David, Jesus the Christ. Christ atones for your sin, and He cleanses your spirit, and now He calls you to serve.
That’s the message of Isaiah 6: When all hope is lost, when it looks like nothing is left—when the king is dead and the world is a mess—God is still working. For He is the great and holy king, and He sits on his throne, high and lifted up. Amen.