Our notion of the supernatural kingdom established by Christ corresponds to some extent with our notions of an earthly kingdom. In order to secure the fruits of Redemption, Christ founded a spiritual society, of which He Himself is the Head—Who teaches its members supernatural truth, Who sanctifies them by His Sacrifice and Sacraments, Who rules and leads them on to supernatural happiness: Who is therefore at once Teacher, Priest, and King. Each of these offices or functions has a holy, or hierarchic, or priestly character, for they are ministrations in the kingdom of God which is holy in its origin, in its growth, and in all its objects. To teach holy things, to make and to dispense holy things, and to lead to the fruition of holy things (sacra docere, sacra dare et facere, ad sacra ducere et perducere), is the triple function of the Head of God’s kingdom.

Of the prophetical or teaching office of Christ we have already treated in the first book of this Manual. We here add only a few remarks.

The Prophets announced Christ as a Teacher of Divine truth to all mankind; Christ Himself claimed this title repeatedly, and exercised this office in many ways during His life on earth. “Behold, I have given Him for a witness to the people, for a leader and a master to the Gentiles” (Is. 55:4). “You call me Master and Lord, and you say well, for so I am” (John 13:13; cf. Matt. 23:10; John 3:31). Christ’s excellence as a Teacher is supereminent. Even as man He is an eye-witness of all that He reveals, and His truthfulness is founded upon His Divinity. His authority is not by delegation: His human words are the words of a Divine Person. He has personal power to prove His mission by miracles. His teaching is not merely external: He has power internally to illumine and move the minds of His hearers. He taught by deed as well as by words: His whole life, with all its incidents, natural and supernatural, being a lesson in holiness. See St. Thomas, 3, q. 42 sqq.