John Flavel, in his The Fountain of Life, wrote:

Salvation, as to the actual dispensation of it, is revealed by Christ as a Prophet, procured by him as a Priest, applied by him as a King. In vain it is revealed, if not purchased; in vain it is revealed and purchased, if not applied.p. 127

Taught in Scripture⤒🔗

Completing the picture of the work of the Messiah as the Anointed One is the office of King. We confess that Jesus Christ is "our eternal King, who governs us by His Word and Spir­it, and defends and preserves us in the salvation obtained for us" (Heidelberg Catechism, q. 31).

All through Scripture it is abundantly clear that Jesus Christ is King. Of this the Church has always sung in the words of Psalm 2. The prophets spoke of it, too. Micah spoke of the Coming One as the Ruler (5:2). Zechariah said, "Behold, thy king cometh unto thee" (9:9). This was also made clear to Mary by the Angel Gabriel:

He shall reign over the house of Jacob for ever; and of his kingdom there shall be no end.Luke 1:33

A Twofold Rule←⤒🔗

However, when we speak of the Kingship of Christ we must be aware that Scripture distinguishes between His rule of power (regnum potentiae) and His rule of grace (regnum gratiae).

The first, Christ's rule of power, is His because He is the Eternal Son of God. It includes rule over everything (Matthew 28:18). His authority is over all men — both Christians and the ungodly, and over all spiritual creatures — angels and devils. He directs all events; He rules over the affairs of all nations.

But when we confess that Christ is our Prophet, Priest and King, we do not mean His rule of power. Rather, we are confessing His rule of grace. This royal power — this rule of grace — that belongs to Christ is His because he purchased His people by the shedding of His blood. As our King He has re­deemed us from sin and death. He rules over His people by His Word and Spirit. This is the rule Paul writes about in Ephesians 1:22, 23: "he (God) put all things in subjection under his feet, and gave him to be head over all things to the church, which is his body and fulness of him that filleth all in all."

To call Christ our King one must be born again (John 3:3, 5). Mere verbal profession will not do:

Not every one that saith unto me, Lord, Lord, shall enter into the kingdom of heaven...Matthew 7:21

A mere attempt at a form of righteousness will not do (Matthew 5:20). But when we are born again then we call Jesus our King and we are kings unto God.

What Kind of King?←⤒🔗

What kind of picture do we get when we use the word "king"? The best way for us to understand the word is to see the kind of king the Bible speaks about.

The proper picture of the king is given, not in 1 Samuel 8:11-18 where we have a picture of the kingly office as it would be deteriorated because of sin, but in Deuteronomy 17:14-20. The king was to be obedient to the Lord (v. 18) and he would be a distinct blessing to the subjects (vv. 19, 20).

Of all the Old Testament monarchs, David stands out as the great king. While he was not a perfect man he was a man after God's heart. As king he pointed to Christ. Ever and again, as the prophets spoke of the Messiah, it was with reference to David. Although Saul and David's royal successors brought suffering (1 Samuel 8:11-18), in David God showed Israel that a righteous deliverer would come. The One who would come would sit on the Throne of David.

Don't forget that David was an oriental monarch — hardly the namby-pamby kind. Nevertheless, he had to rule under God and that meant in the frame­work of God's law. Departures from this way were scorned by God. Under God, the king had some spe­cific duties. He was to lead his people to victory. This meant that he was to gather the army and lead them so that they would do battle to God's glory. Further, the king was responsible for the religious life of the people.

Before the Fall Adam stood as king before God. While his kingdom was a restricted one, i.e., to earth, it was one in which he had plenty to do in service before God (Genesis 1:28, 2:15, 19).

With the Fall everything was changed. Revolt and rebellion made man a king serving under Satan. Hence, Christ had to come. With His coming and by His work God's people are loosed from Satan's dominion.

Is His Kingdom Now?←⤒🔗

All of this raises a very important question: Is His Kingdom now? According to Premillennialists Christ is the head of His Church but He is not the King of the Church. He is the King of the Jews. They substantiate this distinction by an argument based on the two different terms in the Gospels: "Kingdom of Heaven" and "Kingdom of God". They say that these two terms teach two dif­ferent kinds of rules of Christ. The "Kingdom of God" they say refers to the universal kingdom of God. The "Kingdom of Heaven" they say refers to the future mediatorial kingdom of Christ. This rule has not yet come. Hence, there is an aspect of Mes­siah's work which they cannot confess. What they wait for is the re-establishment of the theocracy at the return of Jesus Christ. Then, in their mind, Jesus will be King.

It is perfectly clear, however, that the Bible knows only one kingdom. The two terms are, in reality, used interchangeably (cf. Matthew 4:17 and Mark 1:14; Matthew 11:11 and Luke 7:28; Matthew 5:3 and Luke 6:20).

However, it must be made clear that the kingdom has two aspects — present and future. The future aspect will be the same as the present form of it: the rule of God in the hearts of His own. But when Christ comes again, this Kingdom will be revealed and His rule will be seen in all of its majesty.

He Governs and Defends His People←⤒🔗

Now, what do we mean when we say that Jesus Christ is our King? We confess that powerfully He broke the chains of sin, death and Satan. And we confess that He governs us by His Word and Spirit.

A king is a ruler. He lays down laws and by them he governs his people. Christ is our King. By His Word we learn what He demands. We learn how we are to live and why we are to live that way. The laws of the Kingdom require faith and a life of faith. Holy living — life reflecting Jesus Christ in all ways (1 John 2:6) — is required.

By His Spirit we are made able to live in His way. Through the work of the Holy Spirit we are transformed so that we desire to magnify His grace. He makes us willing subjects of His rule. Through the Holy Spirit applying the Word He rebukes and chastens us and speaks peace to our troubled souls. More and more, we are brought to humbly bow before the King.

A king also defends and preserves his people. The enemies do not gain an upper hand. And God's children have many, many enemies. The devil, the world and our own flesh conspire against us. But no intruders are allowed to destroy His subjects. Our King Jesus preserves and defends us in our daily life. As believers we are engaged in the army of the Lord — the Church Militant. The battles in which we are engaged can be troublesome. Our enemies are bent on our destruction. But Jesus Christ is our King and we live in Him. We need not fear our earth­ly pilgrimage. As King, Christ has said,

I give unto them eternal life; and they shall never perish, and no one shall snatch them out of my hand.John 10:28