Jamieson, Fausset and Brown on Jeremiah 2:8

8. The three leading classes, whose very office under the theocracy was to lead the people to God, disowned Him in the same language as the nation at large, "Where is the Lord?" (See Jr 2:6).

priests--whose office it was to expound the law (Mal 2:6, 7).

handle--are occupied with the law as the subject of their profession.

pastors--civil, not religious: princes (Jr 3:15), whose duty it was to tend their people.

prophets--who should have reclaimed the people from their apostasy, encouraged them in it by pretended oracles from Baal, the Phoenician false god.

by Baal--in his name and by his authority (compare Jr 11:21).

walked after things ... not profit--answering to, "walked after vanity," that is, idols (Jr 2:5; compare Jr 2:11; Ha 2:18).