Jumping straight into the prophecy zone, Isaiah kick-starts with a vision prophesying against the wickedness of Judah, during the reign of a number of its kings.
Isaiah speaks in the voice of God himself—and God, as it turns out, is very displeased.
God says that the people of Judah were raised up as his own children, but they've gone against him.
Unlike a donkey, who is capable of knowing who its master is, Judah is totally rebellious. God rhetorically asks Judah why it hasn't managed to stay true and become obedient, even after it has suffered so many punishments for its crimes.
Zion is now left like a "booth in a cucumber field" (among other things), meaning that it's exposed to outside attack, and has already been ravaged by foreign invasions.
But thanks to God's mercy, he's still left some survivors around. Still, he addresses Judah as though they were the same as the rulers of Sodom and Gomorrah, heading for total annihilation.
Frankly, Scarlet—Then, Snow
God attacks Judah's ritualism. He says that its sacrifices don't please him; in fact, they're abominations. And its ceremonies are a huge waste of time.
God says that he will continue to hide himself from them, refusing to answer their prayers, until the people of Judah make a big 180 degree turn-around.
They need to start walking the walk, instead of just being all ritual and talk. They need to do things like, "defend the orphan, plead for the widow."
This part of the speech ends on a note of promise, with God saying that their scarlet sins will become white as snow. But he warns them, still: if they don't change their ways, destruction will be the order of the day.
Sleeping with the Enemy
God goes on to say more. He says the people are prostituting themselves to wickedness. Failing to take care of the orphan and the widow, they're getting in bed (God uses the adultery metaphor a lot) with murderers and thieves and power-hungry bad guys.
God says that he's going to annihilate all these villains and corrupt people. Pouring out his wrath, God compares it to destroying an alloyed metal, melting it down to make it pure.
He says once this process is complete, the city of Zion will be a beautiful and faithful place once more, like it was in the beginning.
But then again, he reminds them that destruction is still going to be dished out in heaping portions. He says that they'll all regret worshipping sacred trees (we're looking at you, weeping willow), and they themselves will suffer the fate of a tree that withers and dries up.
The wicked deeds done by their strong men will be like a spark that sets them on fire, utterly destroying them.