Concerning Josiah we are here told, 1. That he came to the crown when he was very young, only eight years old (yet his infancy did not debar him from his right), and he reigned thirty-one years (Ch2 34:1), a considerable time. I fear, however, that in the beginning of his reign things went much as they had done in his father's time, because, being a child, he must have left the management of them to others; so that it was not till his twelfth year, which goes far in the number of his years, that the reformation began, Ch2 34:3. He could not, as Hezekiah did, fall about it immediately. 2. That he reigned very well (Ch2 34:2), approved himself to God, trod in the steps of David, and did not decline either to the right hand of to the left: for there are errors on both hands. 3. That while he was young, about sixteen years old, he began to seek after God, Ch2 34:3. We have reason to think he had not so good an education as Manasseh had (it is well if those about him did not endeavour to corrupt and debauch him); yet he thus sought God when he was young. It is the duty and interest of young people, and will particularly be the honour of young gentlemen, as soon as they come to years of understanding, to begin to seek God; for those that seek him early shall find him. 4. That in the twelfth year of his reign, when it is probable he took the administration of the government entirely into his own hands, he began to purge his kingdom from the remains of idolatry; he destroyed the high places, groves, images, altars, all the utensils of idolatry, v. 3, 4. He not only cast them out as Manasseh did, but broke them to pieces, and made dust of them. This destruction of idolatry is here said to be in his twelfth year, but it was said (Kg2 23:23) to be in his eighteenth year. Something was probably done towards it in his twelfth year; then he began to purge out idolatry, but that good work met with opposition, so that it was not thoroughly done till they had found the book of the law six years afterwards. But here the whole work is laid together briefly which was much more largely and particularly related in the Kings. His zeal carried him out to do this, not only in Judah and Jerusalem, but in the cities of Israel too, as far as he had any influence upon them.

The altars of Baalim - How often have these been broken down, and how soon set up again! We see that the religion of a land is as the religion of its king. If the king were idolatrous, up went the altars, on them were placed the statues, and the smoke of incense ascended in ceaseless clouds to the honor of that which is vanity, and nothing to the world; on the other hand, when the king was truly religious, down went the idolatrous altars, broken in pieces were the images, and the sacrificial smoke ascended only to the true God: in all these cases the people were as one man with the king.

And he burnt the bones of the priests upon their altars,.... On which they sacrificed, in detestation of their idolatry, and to deter from it; and this he did according to the prophecy of him, above three hundred and fifty years before:

and cleansed Judah and Jerusalem; from idolatry, and all the monuments of it.

the graves of them that had sacrificed unto them--He treated the graves themselves as guilty of the crimes of those who were lying in them [BERTHEAU].