Christ claimed to build His Church upon a Rock. Apparently, He chose a man to be the figurehead of the Church on Earth, a man once called Simon, renamed Peter. Throughout the centuries, his successors - the popes - have continued to claim the title of Vicar of Christ, and hold the power to bind and loose, especially in matters of infallibility.On this point our Separated Brethren challenge us: how can a Church made up of fallible people claim that a pope, a man like all the rest, be infallible? There have been some blatantly bad popes in history; are they also infallible? Is there any basis in Sacred Scripture for papal infallibility?