A priest is someone set apart to act as God’s representative and to be a liaison between God and his people. The priesthood was established by Moses; the priests served the nation of Israel.
Some versions of the Bible use the phrase chief priests. This is likely a descriptive label and not a title; they can best be thought of as leading priests.
One priest was selected to be the high priest, a position they would hold for life The first high priest was Moses’ brother, Aaron.
Jesus effectively changed the role of the priests. It’s through him that we no longer need a liaison to God, as we can approach God directly. As such, Jesus became our high priest, forever (Hebrews 6:20).
Also see Melchizedek.
Key verse about Priest: “‘you will be for me a kingdom of priests and a holy nation.’ These are the words you are to speak to the Israelites” (Exodus 18:1, NIV)
A lifelong student of the Bible, Peter DeHaan, PhD, wrote the 1,000-page website ABibleADay.com to encourage people to explore the Bible. His main blog and many books urge Christians to push past the status quo and reconsider how they practice their faith in every area of their lives.