Charles Finney emphasizes the profound joy that comes from a deep understanding and relationship with God, as illustrated by the prophet Habakkuk's declaration of joy despite dire circumstances. He explains that true joy in God is rooted in perfect confidence, sympathy with God's will, and recognizing Him as the all-sufficient portion of the soul. Finney argues that this state of mind is essential for peace, salvation, and usefulness in the world, as it allows believers to rejoice in God's sovereignty regardless of their circumstances. He warns against the dangers of seeking happiness in external factors rather than in God Himself, urging believers to cultivate a heart that rejoices in God's character and will. Ultimately, Finney calls for a transformative knowledge of God that leads to unshakeable joy and peace.