2 Chronicles 34:27
Because thine heart was tender, and thou didst humble thyself before God, when thou heardest his words against this place, and against the inhabitants thereof, and humbledst thyself before me, and didst rend thy clothes, and weep before me; I have even heard thee also, saith the LORD.
The words were spoken to Josiah when he heard God's words from the reading of the law pronouncing judgment against Jerusalem and Judah and its inhabitants for breaking the law. Because his heart was tender, he humbled himself before God when he heard that warning, tore his clothes, and wept before Him. His humility included genuine repentance and reform and a prompt seeking of forgiveness and mercy. God acknowledged his humble heart, heard him, and accepted his efforts. God promised him that he would be gathered to his fathers in peace and his eyes would not see all the evil to be brought upon that place and its inhabitants.
His humility did not avert Jerusalem's coming ruin, because the people's long persistence in sin had made punishment unavoidable, so he had to leave future events in God's hands. His later death wounded in battle did not deny the promise of going to the grave in peace, for God did not order him to make war on Necho king of Egypt. After being greatly honored he became self-confident, refused the warning spoken from the mouth of God through Necho's ambassadors to forbear meddling with God, and chose his own way rather than turning back, so God could not shield him from the consequences of fighting a battle he should have had nothing to do with.
The reading of the law in Josiah's days stands as an example of a message from God leading to deep repentance and a return to the Lord, the same response John expected his own message to produce. When God's law exposes sin, people must humble themselves, repent of past wrongdoing, and seek God wholeheartedly, making no compromise with evil and preferring any loss to losing His favor.