Continuing the pottery analogy from the last chapter. When clay is on the wheel it can be re-molded, when it is fired and is broken, it is utterly useless. It’s hardness means it can’t change.
So he breaks a pot and gives a sermon.
The locale is Jerusalem’s rubbish dump, which was constantly burning. It was known as the lake of fire, and was an analogy for their notion of hell.
It was also where child sacrifices to baal and molech occurred. So it was a potent reminder of the extent of Israel’s apostasy.
It’s interesting that when a message is really important to God, he often has people communicate it though performance arts: poetry, dramatic object lessons. Jesus told parables and did things like trashing the temple and cursing a fig tree.
And you can’t say God destroyed Jerusalem out of the blue. There are 50 chapters of these warnings in Jeremiah, not to mention Isaiah and Ezekiel.
You warn people because you care what happens to them.
But sometimes when we are hard enough, the only option God’s has is to break us.