The fall of Jerusalem was followed by assassination, political intrigue, and kidnaping. Specifically, concerning the kidnaping, Jeremiah, along with others, was forced to accompany the rebel leaders to Egypt. They did so, of course, against the better advice of Jeremiah.
For ages, the people of Israel and Judah had been offering sacrifices to other gods. At the Lord’s reproof, some of the people had stopped their idolatry, but it was too little too late. The Lord destroyed their nation. But the people chose not to see it that way. They saw it as the retribution of the false gods they had abandoned. When they arrived in Egypt, bought in to the culture of the Egyptians (including their gods), they began to prosper. So when Jeremiah spoke out against what they were doing, they simply said he was wrong. Their troubles had not been the result of idolatry. They had been the result of a lack of idolatry.
You see how convoluted things get.
Unless one knows the will of God, knows the nature of God, is familiar with his ways, it’s easy to be deceived. Without the knowledge of God, deception comes easily. We can convince ourselves that the sins we are committing are actually in our best interest, and are really the will of the Lord. But truth is not determined by whether we feel justified in our actions: it is determined solely by the eternal plan and will of God and our destiny is determined by whether we know and follow that plan and will.