Samuel Davies preaches about the prevalence of practical atheism in denying the agency of divine providence, exposing the consequences of settling on one's own understanding and neglecting God's sovereignty. He highlights the need for repentance, acknowledgment of God's providence in blessings and calamities, and the dangers of ingratitude and impenitence. Davies emphasizes the importance of prayer, reformation, and gratitude towards God, pointing out the wickedness, pride, and arrogance in denying God's rule over the world. He warns of the impending judgment for a country engulfed in atheism and calls for a return to humble acknowledgment of God's providential care.