The phrase “king of kings” is used in Scripture six times, three of which refer to the Lord Jesus (1 Timothy 6:15; Revelation 17:14, 19:16). The other three (Ezra 7:12; Ezekiel 26:7; Daniel 2:37) refer to either Artaxerxes or Nebuchadnezzar, kings who used the phrase to express their absolute sovereignty over their respective realms (Persia and Babylon). The phrase “lord of lords” is used in Scripture five times, and only referring to God (Deuteronomy 10:17; Psalm 136:3; 1 Timothy 6:15; Revelation 17:14, 19:16). Used together, the two phrases refer only to the Lord Jesus Christ.
In 1 Timothy 6, Paul is wrapping up his letter to Timothy, telling him to fight the good fight and keep his profession of faith. He tells Timothy that he’s to do this “until the appearing of our Lord Jesus Christ,” whom he subsequently refers to as “the blessed and only Sovereign, the King of kings and Lord of lords, who alone has immortality, who dwells in unapproachable light, whom no one has ever seen or can see. To Him be honor and eternal dominion.” The title is used to indicate someone who has the power to exercise absolute dominion over all His realm. In the case of the Lord Jesus, the realm is all of creation. Paul labors to emphasize the solitary nature of Christ’s rule, calling Him the “only” Sovereign, who is “alone” and “unapproachable.” The rule of Jesus is unique and above that of all other rulers.
The other two uses of the phrase, those in Revelation, refer to the final conquest and return of Jesus. The implication is that in the end all other rules will be conquered or abolished, and He alone will reign supreme as King and Lord of all creation and creatures. There is no power, no king, and no lord who can oppose Him and win. There are myriad references to this absolute rule of Jesus, and His preeminence over other rulers, all throughout Scripture, some subtle, some overt. To mention just a few, Isaiah 40:23-24 says that the Lord brings “princes to nothing” and makes earth’s rulers “emptiness.” The mere breath of the Lord will “carry them off like stubble.” Daniel’s vision of the son of man in Daniel 7:13-14 is of one whom he calls “the Ancient of Days” whose everlasting dominion is over all people, nations and languages. In the New Testament, we get a better view of whom these passages refer to when the writer of Hebrews speaks of the Lord Jesus: “He is the radiance of the glory of God and the exact imprint of His nature, and He upholds the universe by the word of His power” (Hebrews 1:3). The next verse speaks of Jesus being “much superior” to the angels. Clearly, His rule over creation is absolute.
Paul makes the point that this rule is derived from Jesus’ sacrifice on the cross. In Philippians 2:5-11, he discusses the extent to which Jesus went to atone for sinners and concludes that this is the reason that “God has highly exalted him and bestowed on him the name that is above every name, so that at the name of Jesus every knee should bow, in heaven and on earth and under the earth, and every tongue confess that Jesus Christ is Lord, to the glory of God the Father” (vv. 9-11).
Finally, in the book of Revelation we see the Kingship of Jesus made manifest. In chapter 5, the Lamb (Jesus) is the only one in all creation found worthy to open the scroll containing the judgments of God (vv. 2-5). In chapter 11, we hear voices in heaven proclaiming that the kingdom of the world has become the kingdom of Christ, and that He will reign forever and ever (v. 15). In chapter 12, we read that the authority of Christ is what causes Satan to be thrown down to earth (vv. 9-10). In chapter 17:12-14, the Lamb conquers all those arrayed against Him, and John stresses that He conquers because He is King of kings and Lord of lords. Finally, in chapter 19, we read of His triumphant coming to strike the nations and tread the winepress of the wrath of God, having the authority to do so because He is King of kings and Lord of lords (vv. 11-16).
Fundamentally, the idea of Jesus being King of kings and Lord of lords means that there is no higher authority. His reign over all things is absolute and inviolable. God raised Him from the dead and placed Him over all things, “far above all rule and authority and power and dominion, and above every name that is named, not only in this age but also in the one to come. And he put all things under his feet and gave him as head over all things to the church, which is his body, the fullness of him who fills all in all” (Ephesians 1:21-23).