J.I. Packer (Concise Theology) notes that one of Calvin’s great contributions to Christian theology was his recognition that in the New Testament the mediatorial work of Jesus is expounded in terms of the threefol office of prophet, priest, and king.

These three aspects are all found in the letter to the Hebrews.  Jesus is the exalted King, Heb 1:3, 13; 4:16; 2:9.  He is the great High Priest who offered himself to God as a sacrifice for our sins, Heb 2:17; 4:14–5:10; chs. 7–10. Also, he is the ‘apostle’ who announces the message of which he himself is the subject, Heb 2:3; 3:1 (cf. Acts 3:22, where Jesus is called a prophet for the same reason.

In the Old Testament, these three roles were fulfilled by separate individuals.  But they now coalesce in Jesus.  He is the all-sufficient Saviour.  Believers are called to obey him as our King, trust him as our priest, and learn from him as our prophet.

Donald Macleod, former Principal of Free Church of Scotland College, asserts the importance of faith in Christ as our prophet and king, as well as our priest:-

It has been a fault of the Reformed churches, going back to Luther, that we have often seen faith exclusively in terms of the priestly activity of Jesus. We have thought of it only in relation to forgiveness and justification. Of course, that is an indispensable element in all faith, but it is not the only element and it is not the point at which every Christian has his or her first experience of faith. It may well be that someone first meets Christ, not in His priestly office, but in His prophetic office or in His kingly office. A sense of guilt is certainly not the point where God’s grace invariably first touches the soul. Faith has other responses besides its response to the priestly victim on the cross of Calvary.

For example, faith in Christ as Prophet means that we believe whatever He teaches because He teaches it. Why do I believe in the infallibility of the Old Testament? I believe it because Jesus Christ said, `The Scripture cannot be broken’ (John 10:35). Faith means the submission of my mind to Christ.

Faith in Christ as King means submission to His commandments and confident repose in His protection. In the twentieth century the human soul is much more preoccupied with insecurity than with the question of guilt. Does life have meaning? Is there purpose? Is there someone in control? It is very important in our twentieth century witness to focus on the sovereignty and kingship of Christ and to ask for a faith that is directed in the first instance not so much towards the sin-bearing sacrifice as towards the cosmos-bearing sovereignty. He’s got the whole world in His hands.

Faith in the Prophet means, then, that my mind submits to him. Faith in the King means that I obey and trust Him. And faith in Christ as sacrifice means that to Him, to His cross, to His death, to His blood, I bring all my sins, because He says, `Come unto me, and I will give you rest’ (Matthew 11:28). In the Old Testament, if someone sinned he had to bring his sacrifice to the Holy Place. Christ is our Holy Place. At Him we confess our sins. With our hands on his Head we confess our sins, and resting our case entirely and exclusively on what He has done we ask that God would forgive and cover our past. The sign of such a faith is peace of conscience: the unshakeable persuasion that our sin has met its full answer and found its full remedy in the obedience of our Saviour. In God’s judgment nothing is relevant to our spiritual standing but what He has done and suffered. Faith, here, means that we add nothing to Jesus.’

A Faith To Live By