After the Second Vatican Council, the impression arose that the pope really could do anything in liturgical matters, especially if he were acting on the mandate of an ecumenical council. Eventually, the idea of the givenness of the liturgy, the fact that one cannot do with it what one will, faded from the public consciousness of the West. In fact, the First Vatican Council had in no way defined the pope as an absolute monarch. On the contrary, it presented him as the guarantor of obedience to the revealed Word. The pope's authority is bound to the Tradition of faith, and that also applies to the liturgy. It is not "manufactured" by the authorities. Even the pope can only be a humble servant of its lawful development and abiding integrity and identity. . . . The authority of the pope is not unlimited; it is at the service of Sacred Tradition. . . . The greatness of the liturgy depends - we shall have to repeat this frequently - on its unspontaneity.
~ Pope Benedict XVI (April 16, 1927 - )