J.C. Ryle emphasizes the critical importance of the heart in one's relationship with God, arguing that a heart cannot be deemed good if it does not reflect righteousness in actions and thoughts. He challenges the notion that people can have 'good hearts at the bottom' while neglecting spiritual duties, asserting that true goodness must be evident in one's life. Ryle outlines the characteristics of a wrong heart, which is naturally inclined to evil, and contrasts it with the right heart, which is transformed by the Holy Spirit and exhibits faith, humility, and a desire for holiness. He calls for self-examination and urges individuals to seek a new heart through Christ, warning against complacency in spiritual matters. Ultimately, Ryle encourages believers to remain hopeful and diligent in their faith, looking forward to the day when they will be fully redeemed.