The sermon emphasizes that true conversion demands a radical break from one's former way of life, as believers are called to walk in a new pattern distinct from the unconverted. Drawing from Ephesians 4:17–19, it argues that the unconverted live in futility of mind, alienated from God due to willful ignorance and hardened hearts, and are characterized by callousness and self-indulgent immorality. These conditions are incompatible with the new life in Christ, which involves renewal of the mind, a restored relationship with God, and transformed behavior. The preacher underscores that genuine faith produces visible change, as seen in the Ephesians' repentance and the Thessalonians' transformation from idolatry to worship of the living God. The call is not merely moral improvement but a fundamental reorientation of life, rooted in the believer's identity in Christ and empowered by the Holy Spirit, so that the Christian life reflects the reality of being a new creation.