What does it mean that God is holy, holy, holy?
The threefold "Holy, holy, holy" appears twice in Scripture — in Isaiah 6:3, where the seraphim cry it before the throne of God, and in Revelation 4:8, where the living creatures repeat it day and night. This is not mere repetition; it is the deepest declaration that heaven can make about the character of God.
The Vision in Isaiah 6
The scene is set "in the year that king Uzziah died" — the leper king, who for all his earthly rank was cut off from the house of the Lord. Against this backdrop of human failure and uncleanness, Isaiah sees Jehovah on His throne.
William Kelly traces the significance of what the seraphim cry and what it produced in the prophet:
William Kelly"No vision more glorious had ever burst on human eyes: but if the attendant burning spirits embraced the fullness of the earth as the scene of His glory, His holiness was their first care and chiefest cry. Activity even in the winged seraphim is not all nor most. Not all six wings did each need for flight, but two only. 'With twain he covered his face, and with twain he covered his feet,' in awe toward God and shame as to himself, in both the reverence that befits them in His presence."
Even these exalted creatures — the burning ones — cannot gaze directly at God's holiness nor display themselves in His presence. Their first and chief occupation is not service, but worship; not flying, but veiling themselves in reverence.
Holiness as God's Essential Nature
H. H. Snell draws out the moral force of the vision — that holiness defines not just what God does, but what He is, and therefore what His presence demands:
H. H. Snell"He heard also the words uttered before the throne; he listened to the converse of creatures there, and found it was 'Holy, holy, holy is the Lord of hosts;' and 'at the voice of him that cried, the posts of the door moved, and the house was filled with smoke.' These things the prophet saw and heard. It was indeed an infinitely holy place. No unclean word was heard there; nothing impure escaped the lips of any; no irreverent action was seen; no presumptuous ways, no angry passions, no foolish actions, no indolent habits, no self-willed manners, were beheld there; for God is holy, and nothing unclean can abide His presence."
C. E. Stuart makes a similar point from the laws of purification in Numbers 19, showing how inflexibly God guarded His own holiness, even where a man might plead he could not have avoided defilement:
C. E. Stuart"Inflexible was the standard of God's holiness, which must be maintained, whatever it might cost His creatures. 'Holy, holy, holy is the Lord of hosts,' cried the seraphim (Isa. 6:3), and here we see exemplified in some degree what that holiness is."
The Threefold Cry and the Trinity
Several writers connect the three-fold repetition with the three Persons of the Godhead. J. G. Bellett draws this out from the way the New Testament references the same vision:
"There the Seraphim cry, 'Holy, holy, holy is the Lord of Hosts!' The New Testament scriptures show that Christ and the Holy Ghost might have been apprehended in the vision and audience, which the prophet then had: for, says St. John, referring to that chapter, 'These things said Esaias, when he saw His (i.e. Christ's) glory, and spake of Him.' And St. Paul, referring afterwards to the same, says, 'Well spake the Holy Ghost by Esaias the prophet unto our fathers.'"
W. H. Vine makes the same connection:
W. H. Vine"John 12:41 says the glory of Jesus was seen then — 'These things said Esaias, when he saw His glory, and spake of Him.' The King is there named; in Acts 28:25 it says, the Holy Spirit then spoke through Isaiah; and the description, 'Holy, holy, holy,' is doubtless descriptive of our thrice holy God, for there it is also said, 'Who will go for US?'"
The Effect: Not Terror, but Worship
In Revelation 4, the redeemed — represented by the twenty-four elders — sit in perfect peace while lightnings and thunderings issue from the throne. J. N. Darby draws out a remarkable truth: the declaration of God's holiness does not make the redeemed tremble — it moves them to worship:
J. N. Darby"When the character of God is opened out in the threefold ascriptions of 'Holy, holy, holy,' does this disturb them? No. So with us, when the full character of God's holiness is seen in His justice, making good His holiness. If in the presence of this holiness I thought there was a spot on me, I could not be at peace before Him. What a blessing to have our home and place of rest where the thrice holy God is!"
"When they hear, 'Holy, holy, holy, Lord God Almighty,' their affections move them, and they fall down immediately in worship. While the judgments move them not the least, their affections take them off their thrones in their falling down to worship. It is the effect of being in perfect undisturbed peace that their affections find utterance in praise."
Holiness and Grace Together
C. H. Mackintosh brings out the crucial counterpart — that this holy God has never ceased in His effort to bring His people into conformity with Himself:
C. H. Mackintosh"God's dwelling place must be holy; and 'without holiness no man shall see the Lord.' There can be no alteration in this. Dispensations may change, but God, blessed be His name, can never cease to be 'the holy, holy, holy Lord God of Israel;' nor can He ever cease in His effort to make His people like what He is Himself. Whether He speak from amid the thunders of Mount Sinai, or in all the gentleness and grace of the blood-sprinkled mercy-seat in the heavens, His object is still the same, — viz., to make and keep His people holy."
William Kelly closes his exposition of Isaiah 6 by noting that the remedy for sin was applied at once — the live coal from the altar:
William Kelly"The effect was immediate on the prophet. It is no longer woe to these or those, but 'woe to me.' He is profoundly touched with a sense of sin and ruin — his own and the people's. But it is uttered in His presence Whose grace is no less than His glory and His holiness, and the remedy is at once applied."
Morrish's Bible Dictionary notes the distinction between the seraphim who bear witness to holiness and the cherubim who execute judgment:
Morrish's Bible Dictionary"The distinction between seraphim and cherubim may be that, while the former bear witness to God's holiness (that is, to His nature), in the latter are exhibited the principles of His righteous government on the earth."
The threefold "Holy, holy, holy" is the supreme declaration of what God is in Himself. It tells us, first, that holiness is not one attribute among many but the very essence of God's nature — the one quality that heaven repeats without ceasing. Second, the three-fold form points to the Trinity: the same vision is ascribed to the Father on His throne, to Christ whose glory Isaiah saw (John 12:41), and to the Holy Spirit who spoke through Isaiah (Acts 28:25). Third, and perhaps most striking, this holiness is not meant to drive us away but to draw us near through grace. The redeemed in Revelation 4 hear it and do not tremble — they worship. And the prophet in Isaiah 6, undone by what he sees, is at once met with the live coal from the altar — the sacrifice that purges sin and sets the conscience free in the very presence of the thrice holy God.