Josiah, however, did not turn away from him; instead, in order to engage him in battle, he disguised himself. He did not listen to Neco’s words from the mouth of God, but went to fight him on the Plain of Megiddo.
It was thirteen years from Josiah's famous passover to his death. During this time, we may hope, thing went well in his kingdom, that he prospered, and religion flourished; yet we are not entertained with the pleasing account of those years, but they are passed over in silence, because the people, for all this, were not turned from the love of their sins nor God...
Commenting on 2 Chronicles 35:20-27
And the archers shot at King Josiah,.... For, though disguised, he appeared to be a general officer, and indeed chief commander, and therefore aimed at him, and pressed him hard: and the king said to his servants, have me away, for I am wounded; as Ahab said, when in the like case, Kg1 22:34.
Nevertheless Josiah would not turn his face from him, but disguised himself, that he might fight with him, and hearkened not unto the words of Necho from the mouth of God, and came to fight in the valley of Megiddo. (l) That is, armed or disguised himself so that he would not be recognized.