Jeremiah 9:15
Therefore thus saith the LORD of hosts, the God of Israel; Behold, I will feed them, even this people, with wormwood, and give them water of gall to drink. Therefore thus saith the LORD of hosts, the God of Israel; Behold, I will feed them, even this people, with wormwood, and give them water of gall to drink.
The wormwood and the water of gall are the bitter punishment and judgment the Lord will bring upon the people. That punishment comes because they forsook His law, refused to obey His voice, walked after the imagination of their own hearts, and walked after Baalim as their fathers taught them. More generally, all who persist in their own way instead of heeding correction and following His counsel will face that same judgment. Directed specifically to those in positions of trust, the warning falls on those who act selfishly and pursue their own ambitions without relying on divine wisdom and power, and such a course calls for repentance and confession.