Sacerdotalism - the heresy.
Sacerdotalism is not just the idea that priests are making a repeat sacrifice of Christ. The Oxford English dictionary states
"Theology relating to or denoting a doctrine which ascribes sacrificial functions and spiritual or supernatural powers to ordained priests" and therefore any belief that saving grace is received through any perceived sacrament, rite, ritual etc is sacerdotalism, described as heresy by all Protestants.
(under construction)
The Roman Catholics and Eastern Orthodox love to make long lists of heresies that infected the early church, like the Judaizer heresy (Galatians) and the docetists, and even invent some that never existed, like the fact that Nicholas in the bible started a sex cult and that was what Jesus meant by the Nicolaitane heesy, so they can deny the obvious conclusion the very word Nico-Laitan described their own heresies. But one early heresy they always miss off their list is the Sacerdotalist heresy, that is their own big heresy!
When and where did the Sacerdotalist Heresy start?
Irenaeus of Lyons ??? - an important historical figure to study, as it is him who is accused of being the inventor of concepts involved with the Recapitulation Theory of Salvation, and the Hypostatic Union Reconciliation theory, yet precise discussion of aspects of the Hypostatic Union did not occur until far later in history. This leads me to believe the heresies were invented later or honed far later, and Irenaeus of Lyons is being used to predate a later sacerdotalist heretical gospel to give it more antiquity.
Did twisting baptism start it?
Perhaps the most likely way the heresy of sacerdotalism started, which I have given evidence is called by Jesus "The doctrine of the Nicolaitans", is in a simple misinterpretation of John 3:5, that is that "born of water" means water baptism, and that therefore baptism is part of the gospel that saves, and that it precedes being born again, and that being born again is brought about through an act of priestcraft, without which "you cannot see or enter the kingdom of God". When this heresy was first stumbled into, foolish men similar to Simon the sorcerer, were practically foaming at the mouth with a foolish idea of them being part of actual salvation of people, and lusted for more rites and rituals to include. Thus over the centuries a ludicrous list of rituals were added.
Did twisting communion start it?
Of course it is also possible that the mass was the beginning of it all, and baptism was added second, who knows? Some fool somewhere was the first heretic who thought "you have no life in you" unless you eat Jesus was literal, and other power hungry fools followed suit adding baptism etc, when it is a metaphor for saving grace, ironically totally denied by the Orthodox who therefore indeed have no life in them. Jesus continually spoke in these comparisons (see this list) and saying you eat Jesus and are not rather filled with his spiritual, is as stupid as interpreting "I am that bread of Life" means Jesus was made of bread, unbelievers are literally goats, and true believers are physically made of salt like Lot's wife.
A matter of choice (or anointing?):
There are two main views on what the Nicolaitan heresy was.
1) Orthodoxy & Catholicism says - it was a hedonistic / antinomian sex cult started by Nicholas from the bible.
2) Protestants & Evangelicals say - it is the creation of a priestly order and laity, "Nico (power over) Laitan (the Laity), via priestcraft. For me this is especially seen in the cranky belief that a Catechumen can wait two years before being given "the ok to be born again" by a priest on a power trip.
There is not definite proof of either from history books. The Orthodox do not believe in being taught directly by the Holy Spirit. They cannot see bible study is a question of relationship with God issue. By my relationship with God, and from the bible definition of the gospel, do I know sacerdotalism is heresy? The answer is 100% yes to that!
Just another Nicholas?
If we accept the Orthodox explanation that Nicholas, in the bible, fell away and became an Hedonistic stroke Antinomianist heretic, why is it that if he could become that, some so called bishop after him in the line of pseud apostolic bishops was not simply an early sacerdotalist heretic himself? The fact is Protestants could not give a hoot about anything but true doctrine, the "other" idea of trash doctrine being given later "because they were empowered to create it" is of no interest to them whatsoever, as why should a new testament equivalent of the Gainsaying of Korah be of any interest from the get-go to anyone?
What is "saved"?
The Orthodox are entirely deceptive about the Protestant use of the word "saved". In fact the Orthodox believe in the exact same thing sometimes, it is just how that state is obtained that is different, By "saved" most Protestants and Evangelicals (except Calvinists and other Antinomianist style heretics) usually mean one of 3 things depending on the context: