Bishops, who are the successors of the Apostles, and priests, who according to their proper office cooperate with the Bishops, have been charged with announcing and teaching that gospel which Jesus and His Apostles first announced and taught, and which this Holy See and all the Bishops united to it have preserved and transmitted pure and inviolate through the centuries.
The holy pastors, therefore, are not the inventors and the composers of this gospel, but only its authorized custodians and its divinely constituted heralds.
--Pope Pius XII,
Ad Sinarum Gentem, 1954
