Duncan Campbell emphasizes the importance of steadfastness in conduct, urging believers to live in a way that reflects their faith and pleases God. He draws on biblical examples such as Enoch, Elisha, and Barnabas to illustrate how consistent and godly conduct can influence others and glorify God. Campbell warns against the dangers of neglecting prayer and the need for a disciplined life that seeks God's presence, as our actions serve as a testimony to the world. He concludes that true discipleship involves imitating Christ and living out our faith in practical ways, as our conduct can either draw others to God or lead them astray.