The sermon titled "Too Long But Not Too Late" focused on King Hezekiah's efforts to restore the celebration of the Passover in a nation that had long neglected it. The sermon emphasized that even in times of spiritual decline, it's never too late to turn back to God. Hezekiah sent out messengers to call the people to repentance and to celebrate the Passover, illustrating the importance of self-examination, the reading of God's word, listening to the right voices, expecting conviction, and finding joy through repentance.