Long term investment.
Jumping back to the seize of Jerusalem, Jeremiah is being held in the kings palace because of his negative talk. The King asks him why, why does he keep saying they will lose?
God has prepared him for this moment by getting him to do a sign showing his long term investment, literally, in the promised land. He’s got him to buy a field during the siege. He’s hidden the deed away, because God has promised one day it will mean something.
The King probably knew they would most likely be defeated. But he just didn’t want to hear it. Jeremiah became an external thing to focus his own fear on.
God and by extension Jeremiah are putting their money on Jerusalem in a tangible way that sort of turns the table on who is the fear monger and who is not.
But it also demonstrates the inequality of power, the king is losing his grip on his, but God never will. Why do we always fall for the earthly power?
Jeremiah is a book about listening to God. He often says the last thing you want to hear.