Life of Pi is about the persistence of faith against all odds. Pi survives a shipwreck in the company of a tiger named Richard Parker, though no one believes this story afterward. Instead, Pi is reduced to telling the story of his survival at sea in a more believable, albeit less magical and mystical, way. This story is not about the faith of any one religion, as Pi is a believer in multiple religions. It is instead about faith and the existence of miracles.
Whether or not this book altered your beliefs in these concepts is up to you. There is no doubt that the author, Yann Martel, suggests that miracles surround us, though they seem to defy reason and rationality. You might have had experiences that have convinced you that miracles can really occur. In other words, this book might remind you of situations that seem miraculous in your own life. If so, this book might change your beliefs about whether miracles are real and whether we should have faith in a divine power.