Brake down. The high place at Bethel was doubtless a building, such as a tabernacle or temple, for it was broken down and burned. Some time had passed since the kingdom of Israel had come to its end, but evidently worship was still being carried on at the shrine Jeroboam had constructed at Bethel.
Burned them. The burning of human bones on an altar would be particularly offensive. Josiah resorted to such an act to show his utter contempt for the terrible form of worship that Jeroboam had instituted in place of the worship of Jehovah, and to make certain that this shrine would never again be used for religious purposes. The bones burned were those of priests who had officiated in the services at these altars (see 2 Chron. 34:5).
Man of God. See 1 Kings 13:1,2.