In light of the fact that someday in the future the nations will stream up to a new Jerusalem with a new temple, hear the word of the Lord, and leave, hammering their swords into ploughs, and their spears into hoes, and learning war no more, the people of Judah are called to walk in the light of the Lord, i.e. to live the future now, in a life of justice and righteousness, being light in a dark world.
Isaiah’s near-death experience and his pronunciation of a judgment oracle on himself becomes the theme of much of his preaching, when he does become a prophet. Before a holy God, the prophet pronounces judgment oracles to the people who have not been practicing righteousness and justice, but the opposite. But the fact that Isaiah will be commissioned as a prophet and will preach to his people shows that he survived this ordeal. In fact, it is the Seraphim who know exactly what to do: his sin needs to be removed—atoned for—so a burning Seraph removes a burning coal from the altar of incense with a tong, and touches it to the prophet’s sinful lips. Thus, he can now join in with the Seraphim in their chorus. And then the Lord of Hosts speaks for the first time in the eerie scene. His servant has been equipped for prophesying so He says, “Whom will I send, and who will go for us?” To which Isaiah with a new lease on life—as one back from the dead–answers the call.
But in some ways, he is to be an anti-prophet, for a prophet was to turn the people to God but Isaiah was to harden their hearts with his preaching. In fact, the people were so far gone spiritually, that Isaiah’s calls to repentance and salvation, would only accelerate the process of corruption, as the people would not listen but become more and more stubborn and obstinate. Called to be God’s servant in the world, they would continue to ignore the call and serve nothing but idols of their own making. So, when Isaiah hears about his call to ministry, he questions, “How long?” The answer comes without equivocation: until the whole nation will be exiled. The nation will be like a giant tree cut down to a stump. And yet there is hope, because there remains a holy seed in the stump, i.e. a sign of life which will someday fulfill God’s plan for the world. Thus, in Isaiah’s ministry, there are not only the judgment oracles, but there is hope for the future, a hope which is found sporadically in the first part of his oracles, but which comes to fruition in the second stage.