Revelation 1:5-6 (NKJV) and from Jesus Christ, the faithful witness, the firstborn from the dead, and the ruler over the kings of the earth. 
To Him who loved us and washed us from our sins in His own blood, and has made us kings and priests to His God and Father, to Him be glory and dominion forever and ever. Amen.

The Royal Priesthood
Understanding this verse is a key to Kingdom advancement and the role that worship takes in it. John says here that Jesus has made us “Kings and Priests.” Our role as ‘Kings’ is to advance the Kingdom of God under the ‘King of Kings’ and to see His glory spread throughout the world. We are a new breed and have the authority under Christ’s throne to spread the gospel to all the earth. This Kingdom advancement does not take on the form that worldly advancement would take. The Kingdom of God is advanced through praise & worship. This is where the role of the Priest becomes so important. The NLT refers to us a “kingdom of Priests” further emphasizing the priestly role we are to take. We are all, everyone who has been brought into the Kingdom of God, a priest and have been called to take on the priestly roles and responsibilities.

The First Priests
To understand the role of the priest, we should look at the Biblical examples of a priesthood and examine their model. Jesus is our High Priest and in Hebrews is revealed as the eternal High Priest:

Hebrews 7:17 And the psalmist pointed this out when he prophesied, “You are a priest forever in the order of Melchizedek.”

Who is this Melchizedek? He is mentioned earlier in Hebrews 7 and briefly in Genesis 14:18, meeting Abram with bread and wine, and then praising God. While this seemingly normal encounter can be easily overlooked, He is stated by David in the psalms as being the standard by which the royal priesthood was set. As we read, this is revealed in Hebrews as being the example Jesus followed. The word “priest” means to “draw near” and we see later in the chapter that the function of the Melchizedek priesthood was to “draw near to God.”

Hebrews 7:19 (NLT) (for the law made nothing perfect), and a better hope is introduced, by which we draw near to God.

David also was a King/Priest and fulfilled his priestly duties, setting up the Tabernacle of David, returning the Ark back to Jerusalem and establishing the sacrifice of praise. He followed in Melchizedek’s model of drawing near to God by praise and worship. He also was followed by Jesus who became the ultimate sacrifice, allowing us to become priests and draw near to the presence of God.

James 4:8 (NKJV) Draw near to God and He will draw near to you.

The Chief Role
So its clear that the chief role of the priest was to “draw near.” The priests in the Old Testament were the ones who would bring the annual sacrifices into the Holy of Holies, covering Israel’s sins and allowing them to come closer to God. David offered God a sacrifice of praise, ministering before the Lord when the Ark of the Covenant was brought back. He set an example through his worship of how all of Israel should respond to presence of God. In the same way, we are called to draw near to God through our praise and our lifestyle of worship. We are under the same Priesthood by the order of Melchizedek that Jesus is now leading us in as High Priest.

For worship leaders this brings new understanding to our role in the act of worship and the responsibilities of this royal priesthood. Just as the early priests brought the sacrifices of the people into the Holy of Holies, we now have the same role of drawing near to God, and encouraging the church to do the same through the sacrifice of praise.