According to the Catechism of the Catholic Church (CCC 1548), priests are...
According to the Bible, there is no "special order" of priests, because EVERY born-again believer is ALREADY a priest.
“And (He, Jesus) hath made us kings and priests unto God and his Father…” (Rev 1:6). Jesus did not just make a few people priests, but, He has made ALL OF *US* into a KINGDOM of priests!
“Ye also, as lively stones, are built up a spiritual house, an holy priesthood, to offer up spiritual sacrifices, acceptable to God by Jesus Christ” (1 Peter 2:5) and later in 1 Peter 2:9 Peter says, “But ye are a chosen generation, a royal priesthood, an holy nation, a peculiar people…” Peter was not talking to an elite class of "priests" but to all the believers - READ IT, and check it out!
So, we see that the priesthood is not some exclusive order, but rather includes every believer in Christ Jesus. Paul tells us to “offer our bodies a living sacrifice…” Only a priest could offer sacrifices to God. So why would Paul tell us to do something we were not authorized to do? Well? Is any of this sinking in yet?
Second, lets look at what the scriptures say about the daily offering of anything pertaining to forgiveness of sin.
“And every priest standeth daily ministering and offering oftentimes the same sacrifices, which can never take away sins: But this man (Jesus), after he had offered one sacrifice for sins for ever, sat down on the right hand of God; From henceforth expecting till his enemies be made his footstool. For by one offering he hath perfected for ever them that are sanctified." (Hebrews 10:11-14)
Now if it was done once in such a perfect way that Jesus could sit down as opposed to the standing and offering and ministering these priests did, why then do we need anything further?
See the article on "The Sin of Being a Roman Catholic Priest"