Then the king summoned all the elders of Judah and Jerusalem.
Josiah had received a message from God that there was no preventing the ruin of Jerusalem, but that he should deliver only his own soul; yet he did not therefore sit down in despair, and resolve to do nothing for his country because he could not do all he would. No, he would do his duty, and then leave the event to God.
Commenting on 2 Kings 23:1-3
And the king sent, and they gathered unto him all the elders of Judah and of Jerusalem. Josiah sent messengers throughout the land, and convened all the principal men in it at Jerusalem. And the king sent, and they gathered unto him all the elders of Judah and of Jerusalem. Josiah sent messengers throughout the land, and convened all the principal men in it at Jerusalem.
And the king sent, and they gathered unto him all the elders of Judah and of Jerusalem. (a) Because he saw the great plagues of God that were threatened, he knew no more speedy way to avoid them, than to turn to God by repentance which cannot come but from faith, and faith by hearing the word of God.