God tells Jeremiah to speak to the people of Judah and Jerusalem, saying that they're cursed unless they remember the covenant they made with God when he led them out of Egypt and into the Promised Land—namely to be obedient to all of God's instructions.
So far, people have failed to live up to the covenant, despite God's warnings and calls for obedience. They are one stubborn bunch.
The people still worship other gods. So of course, God's going to hit them with disaster.
Judah will cry out to the false gods they've been worshipping, but it'll be no use.
God says not to bother praying for the people. He'll see right through any last-minute repentance.
Judah used to be like a fruitful olive tree, but now God's going to burn it down.
Jeremiah says that people conspired to kill him.
At first he had no idea that they were plotting against him, but God clued him in and destroyed Jeremiah's would-be killers.
These conspirators were the people of Anatoth, whom God says he will annihilate: the young men will be killed by the sword, and the rest will starve to death. He's got Jeremiah's back.