Larger Catechism, week 10

Q. 42. Why was our Mediator called Christ?
A. Our Mediator was called Christ, because he was anointed with the Holy Ghost above measure,[161] and so set apart, and fully furnished with all authority and ability,[162] to execute the offices of prophet,[163] priest,[164] and king of his church,[165] in the estate both of his humiliation and exaltation.

Q. 43. How doth Christ execute the office of a prophet?
A. Christ executeth the office of a prophet, in his revealing to the church,[166] in all ages, by his Spirit and Word,[167] in divers ways of administration,[168] the whole will of God,[169] in all things concerning their edification and salvation.[170]

Q. 44. How doth Christ execute the office of a priest?
A. Christ executeth the office of a priest, in his once offering himself a sacrifice without spot to God,[171] to be reconciliation for the sins of his people;[172] and in making continual intercession for them.[173]

Q. 45. How doth Christ execute the office of a king?
A. Christ executeth the office of a king, in calling out of the world a people to himself,[174] and giving them officers,[175] laws,[176] and censures, by which he visibly governs them;[177] in bestowing saving grace upon his elect,[178] rewarding their obedience,[179] and correcting them for their sins,[180] preserving and supporting them under all their temptations and sufferings,[181] restraining and overcoming all their enemies,[182] and powerfully ordering all things for his own glory,[183] and their good;[184] and also in taking vengeance on the rest, who know not God, and obey not the gospel.[185]