High Quality Content by WIKIPEDIA articles! The universal priesthood or the priesthood of all believers is a Christian doctrine believed by various Protestant denominations to be derived from several passages of the New Testament. The exact meaning varies from denomination to denomination, but generally entails a doctrinal responsibility or right to preach and expound the Christian faith, and this is appointed to every member of the church. It first came to the public eye when Martin Luther and his followers wrote, preached, and sang about a priesthood of all believers.