Erlo Stegen's sermon 'Ahab Exposed' warns against the dangers of false prophets and the consequences of turning away from God, as exemplified by King Ahab and Queen Jezebel. Ahab, influenced by his wicked wife, sold himself to sin and ultimately faced God's judgment, illustrating the peril of allowing evil to dominate one's life. The sermon emphasizes the importance of self-examination to ensure one is truly aligned with God's will, rather than being deceived by false assurances. Stegen also highlights the destructive nature of unholy relationships and the need for discipline in upbringing to prevent future ruin. The tragic end of Ahab and Jezebel serves as a stark reminder of the consequences of living outside of God's authority.