5 The word translated “woe” here (ʾôy; GK 208) is different from that used several times in ch. 5 (hôy [GK 2098], vv. 8, 11, 20–22), though they are similar in form and pronunciation and identical in meaning. They are, in fact, synonyms, each possessing various nuances ranging from a threat to a sigh. If this part of the book has been arranged with an eye more to its message than to its chronology, this “woe” may have been viewed as the climax of the series that began at 5:8. The reference in this verse to the people’s sin strengthens this possibility, the more so as sins of the tongue have found their place in ch. 5 at least twice (5:18–20) and possibly a third time, for acquittal (5:23) was made known by a pronouncement of the judge.
This verse teaches us that in order to be an effective channel for God’s penetrating word, the power of that word must be felt in the person’s own conscience. Wildberger (in loc.) says, “This terror is itself an element of the theophany (cf. Ge 32:30; Ex 3:6; Jdg 6:22; 13:22). Those who utter such a cry of woe about themselves are witnessing to the fact that their very existence is threatened” (cf. also Watts, in loc.).
It is true that the lips of the prophet were destined to proclaim God’s truth; but if he was in the temple at worship (see comment on v. 1), the primary reference may be to the defiled lips of the worshiper (cf. 1:15; 29:13). The people of the OT always felt a deep apprehension at the prospect of seeing God (Ge 32:20; Ex 33:20; Jdg 6:22; 13:21–22). This must have been underlined still more for Isaiah as he saw even the unfallen seraphs covering their faces in the presence of the Most High.
In the presence of a holy God sinners feel ‘utterly at a loss’ (a popular phrase not dissimilar to the one Isaiah uses in verse 5)—like Isaiah here. When Simon Peter begins to realize that to be with Jesus is to be in the presence of God, he requests, ‘Depart from me, for I am a sinful man’ (Luke 5:8). Holiness and sin don’t mix. They never will. Sadly, there will be a day when sinners will hear the Lord Jesus say to them, ‘Depart from me’ (Matt. 25:41).
But sin can be atoned for—through sacrifice. The word ‘atoned’ in verse 7 comes from a Hebrew word that can mean ‘to cover’. It describes how sin is dealt with. Theologians argue about the main meaning of the word. Covering over, paying a ransom price and wiping clean are all pictures that the word can be associated with, and they all give a slightly different perspective on what is involved in dealing with sin. It is clear, though, what the day of atonement was designed to portray. This was the day when the sins of Israel were symbolically transferred to a scapegoat, which was then sent away into the wilderness, never to be seen again. Sin had been carried away. Whether you think of atonement as sin being covered (see Ps. 32:1; 85:2), the price of sin being paid (Col. 2:14; 1 Tim. 2:6) or the stain of sin being cleansed (Ps. 51:2; 1 John 1:7), it was gone! Whether into the depths of the sea (Mic. 7:19), behind God’s back (Isa. 38:17) or as far as the east is from the west (Ps. 103:12), it was gone.
Something else that the day of atonement made clear was that the vital ingredient for atonement was blood (Lev. 17:11). That was because blood represented the life of the sacrificial victim offered up in place of the worshipper. It pointed forward to ‘the precious blood of Christ’ (1 Peter 1:19), which seals the new covenant, ‘poured out for many for the forgiveness of sins’ (Matt. 26:28). The blood of goats and bulls could make people ceremonially clean, but it is the blood of Christ alone that can effectually cleanse from all sin (1 John 1:7).
In Alaska in the late nineteenth century the Stickeen and Sitka Indians welcomed Christian missionaries, at least in part because they were so familiar with the concept of atonement. At one point in their history fighting between the two tribes was so serious that their future looked to be under threat. A Stickeen chief stood in an open place between the two camps and asked to speak to the leader of the Sitkas. He said,
‘My people are hungry. They dare not go to the salmon-streams or berry-fields for winter supplies, and if this war goes on much longer most of my people will die of hunger. We have fought long enough; let us make peace. You brave Sitka warriors go home, and we will go home, and we will all set out to dry salmon and berries before it is too late.’
The Sitka chief replied, ‘You may well say let us stop fighting, when you have had the best of it. You have killed ten more of my tribe than we have killed of yours. Give us ten Stickeen men to balance our blood-account; then, and not till then, will we make peace and go home.’
‘Very well,’ replied the Stickeen chief, ‘you know my rank. You know that I am worth ten common men and more. Take me and make peace.’
And the Stickeen chief was shot down. When they heard the gospel and it was explained to them that all mankind had gone astray, broken God’s laws and deserved to die, but then God’s Son came forward and offered himself as a sacrifice, they said, ‘Yes, your words are good … The Son of God, the Chief of chiefs, the Maker of all the world, must be worth more than all mankind put together; therefore, when His blood was shed, … salvation … was made sure.’
Sin, then, can be atoned for, through sacrifice. And when sin is atoned for, guilt is taken away. Sometimes a sense of guilt lingers, but the guilty verdict has been overturned for good (1 Cor. 1:8). This is how a man of unclean lips can become the Lord’s spokesman; how a sinful nation (1:4) can become a righteous nation (26:2); and how we who ‘fall short of the glory of God’ (Rom. 3:23) can ‘rejoice in hope of the glory of God’ (Rom. 5:2).
6:5 / Holiness also means purity. Yahweh’s holiness could make a mere creature simply draw back. But because of who Yahweh is, holiness comes to have moral connotations (see on 5:16). Isaiah draws back from God’s holiness not just because of God’s awesome splendor and his own creatureliness. He also draws back because God is just and righteous and he and his people are polluted (tame’), like the king who died that year (2 Kgs. 15:5). They do not fulfill the demands of Psalm 24. The fact that his lips were the part of his person especially involved in serving God as a prophet may lie behind his linking pollution with his lips. But he links his pollutedness with his people’s, suggesting that he is identifying the pollution of his lips with Judah’s. He has already referred to a number of the wrongs of their lips (e.g., 1:15, 23; 2:6; 3:8; 5:19, 20, 24). In the context of worship, the first of these (1:15) would have been especially relevant. Whichever it is, Isaiah finds that a vision of the holy God shuts the mouth.
6:6–7 / Isaiah’s instinct to infer that holiness will be the end of him turns out to be mistaken. He also learns that holiness can mean forgiveness. In keeping with his stress on fire as a means of judging/purging (1:25; 4:4), a coal from the incense altar touches the part of Isaiah’s body that he recognized to be the place of pollution (cf. Num. 16:46–47). The high and lofty One (the same phrase as in v. 1) dwells in a high and holy place, but also with those who are crushed and lowly in spirit (57:15). Merciful grace belongs as much to the essence of God’s holiness as justice and purity. Once more, a return to Yahweh is not the only requirement for a restored relationship with Yahweh, as chapter 1 might have seemed to imply (guilt/sin recur from 1:4). People who do nothing and presume on God’s forgiveness indeed fail to experience it; those who acknowledge the justice of God’s judgment and turn from the ways that earned it can escape it.
The sign of cleansing that Isaiah receives is absurdly inadequate. How could being touched with a coal effect this sort of purification? The insufficiency of the sign highlights the fact that the cleansing originates within the person of the holy God. Sacramental rites such as this are the means by which Yahweh incarnates grace to humankind.
 Grogan, G. W. (2008). Isaiah. In T. Longman III, Garland David E. (Eds.), The Expositor’s Bible Commentary: Proverbs–Isaiah (Revised Edition) (Vol. 6, pp. 507–508). Grand Rapids, MI: Zondervan.
 Thomson, A. (2012). Opening Up Isaiah (pp. 34–37). Leominster: Day One.
 Goldingay, J. (2012). Isaiah. (W. W. Gasque, R. L. Hubbard Jr., & R. K. Johnston, Eds.) (pp. 59–60). Grand Rapids, MI: Baker Books.