Charles Ellicott Commentary Jeremiah 23:34

"And as for the prophet, and the priest, and the people, that shall say, The burden of Jehovah, I will even punish that man and his house." — Jeremiah 23:34 (ASV)

That shall say, The burden of the Lord.— The language thus put into the mouths of the false prophets is not that of derision, but of boastful assumption. It is for this reason that the boaster will, in due time, be punished.