It was John Calvin who brought the so-called ‘threefold office’ of Christ into prominence. The threefold office presents Jesus Christ as prophet, priest, and king, who in his saving work, fulfilled all the anointed offices of the Old Testament. For Calvin, ‘the Son of God, therefore, is not properly called Christ apart from his office, for it is there, in his official capacity, that he manifests as the true fulfilment of the offices of the Old Testament his threefold work as prophet, priest, and king.’
The threefold office of our Lord is the divinely revealed solution to human sin:
The threefold misery of men introduced by sin-ignorance, guilt, and tyranny and bondage by sin-required this conjunction of a threefold office. Ignorance is healed by the prophetic; guilt by the priestly; the tyranny and corruption of sin by the kingly office. Prophetic light scatters the darkness of error; the merit of the Priest takes away guilt and procures a reconciliation for us; the Power of the King removes the bondage of sin and death. The Prophet shows God to us; the Priest leads us to God; and the King joins us together and glorifies us with God. The Prophet enlightens the mind by the Spirit of illumination; the Priest by the Spirit of consolation tranquilizes the heart and conscience; the King by the Spirit of sanctification subdues rebellious affections. (Francis Turretin)
Christ Our Prophet
Christ’s prophetic office means, in effect, that Christ represents God to man. Jesus is the light of the world (Jn 1:4-5), who comes to show us God the Father (Jn 14:9). Moses foretold of a great prophet that “the Lord your God will raise up for you among your brothers. You must listen to him” (Dt 18:15). Peter applies this passage to our Lord (Acts 3:22-23). Jesus speaks of Himself as such a prophet (Lk 13:33), and expressly claims to speak only what His Father told Him to say (Jn 12:49-50; 14:10, 24; 15:15; 17:8, 20). Jesus speaks of the future (Mt 24:3-35), and speaks with an amazing authority unlike all others (Mt 7:29). Indeed, our Lord’s words are backed by the power of God, for His mighty works confirm the truth of His message (Mt 21:11, 46; Lk 7:16, 24:19; Jn 3:2, 4:19, 7:40, 9:17). In John 6:14 we are told that “after the people saw the miraculous sign that Jesus did, they began to say, ‘Surely this is the Prophet who is to come into the world.’”
Christ’s prophetic work does not cease at his Ascension. It continues through the operation of the Holy Spirit. As the Spirit of Christ, He is the one who “will convict the world of guilt in regard to sin and righteousness and judgment” (Jn 16:8). As Christ is the Word incarnate, and the central figure in biblical revelation, so too we cannot divorce the work of his Spirit from the written word.
Christ our prophet certainly speaks to us today through the pages of His word, the Holy Spirit opens our minds and our hearts to hear our Lord’s voice as we read His word and hear it expounded. Therefore in Scripture, God’s word written, we find a voice that is certain, not like the extemporaneous musings of those today who claim to speak for God.