What is unam sanctam?

"Unam Sanctam" is a papal bull issued by Pope Boniface VIII in 1302, asserting the supremacy of the papal authority over secular rulers. It famously declares that there is one holy church and that salvation is only found within it, emphasizing the necessity of obedience to the Pope. This document was significant in the context of the ongoing conflict between the papacy and monarchies, particularly King Philip IV of France. It underscored the Church's claim to spiritual and temporal power during the medieval period.