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.

He burnt the bones of the priests - כומריא kumeraiya, the kemarim, says the Targum. See this word explained, Kg2 23:5 (note).

And so did he in the cities of Manasseh, and Ephraim, and Simeon, even unto Naphtali,.... Which though they belonged to the ten tribes, yet these being carried captive by the king of Assyria, they that were left became subject to the kings of Judah; see Gill on Kg2 23:19,

with their mattocks round about; or hammers or mauls, as Kimchi, or pick axes, such sort of instruments as were used in demolishing altars and images: the Targum is,"in the house of their desolation;''

and so other versions, "in their desolate places" (x), which were become such, the inhabitants being carried captive, and few left behind.

(x) "in desolatis locis suis, vel eorum", Montanus, Tigurine version, Rambachius.

he burnt the bones of the priests upon their altars--A greater brand of infamy could not have been put on idolatrous priests than the disinterment of their bones, and a greater defilement could not have been done to the altars of idolatry than the burning upon them the bones of those who had there officiated in their lifetime.