John Gill emphasizes the importance of diligence in the Christian faith, urging believers to actively cultivate virtues alongside their faith. He explains that while faith is a gift from God, it should not stand alone but be accompanied by good works that reflect true belief. Gill highlights the necessity of knowledge in understanding God's will and performing good works, warning against zeal without knowledge. He encourages Christians to embody virtues that stem from the grace of God, which differ from mere moral actions. Ultimately, the sermon calls for a holistic approach to faith that integrates belief, virtue, and knowledge.