Saint Peter is shown holding a key and a book, symbolizing his authority to bind and loose on earth as given by Christ (Matthew 16:19) and his role in spreading the Gospel. The key represents his leadership as the first pope and guardian of the Church, while the book reflects his mission to teach the truth of Christ. His calm, upward gaze reflects both faith and humility, reminding believers of his transformation from fisherman to apostle, and his calling to guide the early Christian community with courage and conviction.