Christians serve the King and will someday reign with Him in His Kingdom.
In Exodus 19:5-6 God says to Israel, "If you will indeed obey My voice and keep My covenant, then you shall be My own possession among all the peoples . . . and you shall be to Me a kingdom of priests and a holy nation." They were to be both priests and royalty, but they violated the covenant and forfeited those privileges. Now, according to Peter, Christians are the royal priesthood of God.
The Greek word translated "royal" in 1 Peter 2:9 was used of a royal palace, sovereignty, crown, or monarchy. In this context it refers to royalty in general. We speak of the royal house of England or France, meaning not a building but a sphere of dominion. So it is with God's spiritual house (v. 5). Believers serve the King and will also reign with Him in His sphere of dominion.
That is affirmed elsewhere in Scripture. In the book of Revelation we read, "Thou hast made them to be a kingdom and priests to our God; and they will reign upon the earth" (Rev. 5:10); and, "Blessed and holy is the one who has a part in the first resurrection; over these the second death has no power, but they will be priests of God and of Christ and will reign with Him" (Rev. 20:6).
Your royal position has some practical implications for the way you live each day. For example, when dealing with the problem of litigation among Christians, Paul said: "Does any one of you, when he has a case against his neighbor, dare to go to law before the unrighteous, and not before the saints? Or do you not know that the saints will judge the world? And if the world is judged by you, are you not competent to constitute the smallest law courts? Do you not know that we shall judge angels? How much more, matters of this life?" (1 Cor. 6:1-3).
Never forget who you are in Christ, and don't let sin or the world distract you from your priestly role.
Suggestions for Prayer
Memorize 1 Timothy 4:12. Ask God to make you a better example of one who represents His royal priesthood.
For Further Study
Read Genesis 14:18-20 and Hebrews 7:1-17. Who was Melchizedek and what was unique about his priesthood?