God has made you a King and a priest unto him, now that you are saved and you know Him as Lord and Saviour.
1Peter 2:9 But ye are a chosen generation, a royal priesthood, an holy nation, a peculiar people; that ye should shew forth the praises of him who hath called you out of darkness into his marvelous light: 10 which in time past were not a people, but are now the people of God: which had not obtained mercy, but now have obtained mercy.
God is talking about you that is born again: You are a royalty; you are more than the royalties of this world. God has chosen you out of many and he has made you a priest unto him, Christ being the Chief Priest.
When one is a priest before God it means they have been brought to a place where they can communicate with God and also offer sacrifices to God. This implies that when pray for yourself and for others, God hears you. For through Christ we have access to God (Romans 5:1).
God looks at you as a king, and he wants to deal with you as a King. This is because Christ Jesus has made you a king and a priest to God.
Revelation 1:6 And hath made us kings and priests unto God and his Father; to him be glory and dominion for ever and ever. Amen.
When the bible says Jesus is the King of Kings. He is not taking about the royals of this world, as in those leading kingdoms on the earth like the Kabaka of Buganda, the Imorimori of Teso land or the Kyabazinga of Busoga which are Chiefdoms and Kingdoms in Uganda.
God is instead referring to you in particular; we are the heavenly Kings on earth.
Through his son Jesus God has brought us to a place of kingship and rulership. Earthly kings occupy earthly positions and it is true that God appoints kings over men.
However, the earthly Kings are not heavenly kings. They have to get born-again to become kings in God.
God has brought the church to a place of dominion, begin to speak, live and declare things like kings do. Where the word of a King is, there is power (Ecclesiastes 8:4).
We have been called to the glorious and Kingly life in Christ.