2 Kings 23:20

“And he slew all the priests of the high places that were there, etc.] The idolatrous priests who sacrificed to Baal, and other Heathen deities; for as for others that burnt incense in high places, yet to the true God, those he spared, though they were not suffered to officiate at the altar of God: the others he slew upon the altars; where they sacrificed: and burnt men’s bones upon them: the bones of the priests, and worshippers of idols, as he had done at Bethel: and returned to Jerusalem; after he had gone through the land, both of Judah and Israel, and abolished idolatrous worship everywhere.”

“A parenthesis giving the earlier reforms of Josiah. 2 Kings 23:4 The priests of the second order - This is a new expression; and probably refers to the ordinary priests, called here “priests of the second order,” in contrast with the high priest, whose dignity was reviving (2 Kings 12:2 note). The vessels - This would include the whole apparatus of worship, altars, images, dresses, utensils, etc., for Baal, etc. (2 Kings 21:3-5 notes). The ashes of the idolatrous objects burned in the first instance in the “fields of Kidron” (i. e., in the part of the valley which lies northeast of the city, a part much broader than that between the Temple Hill and the Mount of Olives) were actually taken to…”

“The priests - By this relation it appears, that after the departure of the king of Assyria, divers of the Israelites who had retired to other parts, and kept themselves out of the conqueror's hands, returned together with their priests to their own land, and to their old trade, worshipping idols; to whom, peradventure, they ascribed this their deliverance from that judgment which Jehovah had brought upon them. And burnt - According to that famous prophecy, Kg1 13:1-2. 4 Kings (2 Kings) 23:22”

“he slew: or, he sacrificed, Kg2 10:25, Kg2 11:18; Exo 22:20; Deu 13:5; Kg1 13:2, Kg1 18:40; Isa 34:6; Zac 13:2, Zac 13:3 burned: Ch2 34:5 4 Kings (2 Kings) 23:21”