John Nelson Darby emphasizes the importance of living a life that reflects Christ's glory, urging believers to manifest His life in their actions and hearts. He reminds us that we are in the presence of the world to represent Christ, who intercedes for us before God. Darby stresses the need for earnestness in our faith, especially in challenging times, and challenges Christians to truly embody their faith so that others may understand the essence of Christianity. He calls for a deep sense of Christ's love, encouraging believers to live for Him and to share His message of redemption with those who do not know Him.