One way of understanding the work of Jesus Christ that is typically associated with the Reformed tradition is the concept of munus triplex, or the “threefold office” of Christ. This refers to his work as prophet, priest, and king, and is expressed like this in the Westminster Shorter Catechism:
Q. 23. What offices doth Christ execute as our Redeemer?
A. Christ, as our Redeemer, executeth the offices of a prophet, of a priest, and of a king, both in his estate of humiliation and exaltation.
Q. 24. How doth Christ execute the office of a prophet?
A. Christ executeth the office of a prophet in revealing to us, by his Word and Spirit, the will of God for our salvation.
Q. 25. How doth Christ execute the office of a priest?
A. Christ executeth the office of a priest in his once offering up of himself a sacrifice to satisfy the divine justice, and reconcile us to God, and in making continual intercession for us.
Q. 26. How doth Christ execute the office of a king?
A. Christ executeth the office of a king in subduing us to himself, in ruling and defending us, and in restraining and conquering all his and our enemies.
This idea is also presented in the Heidelberg Catechism and throughout Reformed theology. There can be a tendency, however, to impose artificial and sometimes arbitrary distinctions upon Christ’s actions in order to identify something as the function of one particular office. For example, when Jesus taught the crowds, was he wearing his “prophet” hat only? When he cleared the Temple, was he on the clock as “king”? Or is the concept of munus triplex more profound and holistic than that?
Here are some wise words from Herman Bavinck on the unity of Christ’s threefold office that I think are helpful:
Many theologians, however, object to the threefold office of Christ on the ground that one office cannot be distinguished from the others. True, no single activity of Christ can be exclusively restricted to one office. His words are a proclamation of law and gospel and thus point to the prophetic office; but he speaks as one having authority, and all things obey his command (Mark 1:22; 4:41; Luke 4:32; etc.); he calls himself king, comes into the world to bear witness to the truth (John 18:37). His miracles are signs of his teaching (John 2:11; 10:37; etc.) but also a revelation of his priestly compassion (Matt 8:17) and his royal power (Matt 9:6, 8; 21:23). In his intercessory prayer not only his priestly but also his prophetic and royal offices are evidenced (John 17:2, 9-10, 24). His death is a confession and an example (1 Tim 6:13; 1 Pet 2:21; Rev 1:5), but also a sacrifice (Eph 5:2) and a demonstration of his power (John 10:18).
Dogmatics has been perplexed, therefore, as to what things from Jesus’ life and works had to be assigned to each office in particular. Usually treated under [the heading of] Christ’s prophetic office were his teaching, predictions, and miracles; under [the heading of] his priestly office, his acts of sacrifice, intercession, and blessing. Remaining, then, for his royal office in the state of humiliation there was no more than the tribute offered by the magi, the entry into Jerusalem, the appointment of the apostles, in institution of the sacraments–isolated facts that can in part just as well be assigned to the other offices. Even more difficult became the description of the difference in the state of exaltation. For though Jesus’ prophetic activity is continued in teaching his church by Word and Spirit, he rules and protects his church by these two as a king also, and his high priestly intercession is not an entreaty but an expression of royal will (John 17:24).
It is, accordingly, an atomistic approach, which detaches certain specific activities from the life of Jesus and assigns some to his prophetic and others to his priestly or royal office. Christ is the same yesterday, today, and forever. He does not just perform prophetic, priestly, and kingly activities but his himself, in his whole person, prophet, priest, and king. And everything he is, says, and does manifests that threefold dignity.
Granted, in the one activity it is more his prophetic office that is evident to us, and in another it is his priestly or kingly office that stands out; and it is also true that his prophetic office comes to the fore more in the days of the Old Testament and during his days of traveling around on earth, his priestly office more in his suffering and death, his kingly office more in his state of exaltation. But actually he bears all three offices at the same time and consistently exercises all three at once both before and after his incarnation, in both the state of humiliation and that of exaltation.
–Reformed Dogmatics, vol. 3, p. 366-7 (boldface added).
I find Bavinck’s discussion to be an accurate and apt reminder of the depth and wonder of Christ’s work. He is not disagreeing with the approach of the Shorter Catechism when it identifies specific works attributable to each office, but warning against unnecessarily divorcing them from each other or, worse, somehow pitting them against one another.
Jesus Christ is prophet, priest, and king, not by taking turns or working different shifts, but “in his whole person” and in everything he does.