By virtue of the fact he's the Catholic Pope. You can be christian w/o being catholic, but to be catholic is to accept the teachings of the church hierarchy - that's the whole point of the religion. The distinction between cath & prodestant, I think, is that a prod thinks you can redeem yourself through connecting with your god, while the catholic religion requires communication through the church hierarchy for such redemption. To be rejected by the catholic church or excommunicated is by their terms condemned to hell, while a prod can find redemption independently of the church - though the church is still important.