It's just my opinion, but I think the "who" needs to be well established and understood before the "how's" are focused upon. I think "being a priest" carries with it, for many people, the implication that there are performances to be learned and perfected. (How do you think the RCC got so screwed up?)
Willie,
Because this doctrine -- the priesthood of all believers -- is generally neglected, it is wise to introduce it to Christians by giving
just an overview of the OT priesthood and then explaining that God is finished with that system altogether, because of the New Covenant. So what does someone who has no clue need to know?
1. Israel was chosen by God to bring Messiah (the Christ) into the world.
2. Christ was the Lamb of God who was slain from before the foundation of the world.
3. Christ would come to earth "when the fulness of time was come" to die for the sins of the world on the cross.
4. Between the time that Moses brought Israel out of Egypt and Christ died on the cross, God gave Israel and the world "the shadows" of His one great sacrifice for sins.
5. Those shadows were the animal sacrifices (including the Passover lamb), the offerings, the feasts, and everything connected with them.
6. The blood of animals only "covered" sin. The Lamb of God "took away" the sin of the world.
7. In order to properly represent the heavenly pattern, God first instituted the Tabernacle and then the Temple in Jerusalem.
8. He also created the Levitial priesthood and the ministry of the Levites to assist them in offering the sacrifices.
9. When Christ died on the cross, this whole Mosaic System came to an end. Therefore the veil in the Temple was torn in two from top to bottom by God Himself.
10. In 70 AD God allowed the Romans to destroy Jerusalem and the Temple and to scatter the Jews throughout the world. This was the actual end of the Mosaic System.
11. From the day of Pentecost following Christ's resurrection, God created a new entity -- the Church (Jew and Gentile in one Body) -- to become a Royal Priesthood.
12.
Every individual in the Church is a king and a priest (1 Pet 2:1-10) and required to offer "spiritual sacrifices".
Naturally, whoever presents this must bring out the Scriptures which support these truths. Without the Scriptures, these truths become opinions.