J.R. Miller emphasizes the importance of embodying the inner beauty of Christ rather than focusing on physical representations. He highlights that true Christian life involves growing into the loveliness of Christ, which includes love, humility, and unity among believers. Miller points out that quarrels and divisions among Christians mar the spirit of the church, urging the need for harmony and mutual respect. He draws from Paul's teachings to illustrate that having the mind of Christ means living in love and service to others, reflecting Christ's character in our actions. Ultimately, Miller calls for Christians to prioritize the qualities of Christ in their lives, ensuring that their actions reflect His grace and compassion.