"The Priesthood of All Believers"
In the "On the Square" column of the First Things website, Peter Leithard has an article on the Lutheran doctrine of "the Priesthood of All Believers". It is quite a good read, and I think that even Catholic readers will be edified by it, especially the reflections on the Aaronic priesthood, and how that reflects in the priestly character of the Church today.
The Second Vatican Council embraced its own version of this classic Reformation doctrine. Essentially, it reclaimed the scriptural teaching that the whole assembly of the faithful are a "royal priesthood" (1 Peter 2:9).
"Christ instituted this new covenant, the new testament, that is to say, in His Blood, calling together a people made up of Jew and gentile, making them one, not according to the flesh but in the Spirit. This was to be the new People of God. For those who believe in Christ, who are reborn not from a perishable but from an imperishable seed through the word of the living God, not from the flesh but from water and the Holy Spirit, are finally established as "a chosen race, a royal priesthood, a holy nation, a purchased people . . . who in times past were not a people, but are now the people of God"...
Christ the Lord, High Priest taken from among men, made the new people "a kingdom and priests to God the Father". The baptized, by regeneration and the anointing of the Holy Spirit, are consecrated as a spiritual house and a holy priesthood, in order that through all those works which are those of the Christian man they may offer spiritual sacrifices and proclaim the power of Him who has called them out of darkness into His marvelous light. Therefore all the disciples of Christ, persevering in prayer and praising God,(103) should present themselves as a living sacrifice, holy and pleasing to God. Everywhere on earth they must bear witness to Christ and give an answer to those who seek an account of that hope of eternal life which is in them." Lumen Gentium 9,10
However, the Council continued to uphold the distinction between the "ministerial priesthood" and the "common priesthood of the faithful" in the following way:
Though they differ from one another in essence and not only in degree, the common priesthood of the faithful and the ministerial or hierarchical priesthood are nonetheless interrelated: each of them in its own special way is a participation in the one priesthood of Christ. The ministerial priest, by the sacred power he enjoys, teaches and rules the priestly people; acting in the person of Christ, he makes present the eucharistic sacrifice, and offers it to God in the name of all the people. But the faithful, in virtue of their royal priesthood, join in the offering of the Eucharist. They likewise exercise that priesthood in receiving the sacraments, in prayer and thanksgiving, in the witness of a holy life, and by self-denial and active charity.
The distinction between the "priesthood of all believers" and the "office of the ministry" can also be found in Lutheran doctrine, with a corresponding teaching that the difference is one of "essence" and not only "degree", yet Lutherans are usually a little less inclined to actually ascribing the categories of "priesthood" to the "office of the ministry". They see the latter purely in ministerial terms, and not (generally) in priestly terms. This is because (again, generally speaking), they see the Aaronic priesthood to have been replaced soley with "the preisthood of all believers", leaving no place for a order of priesthood within the priestly people of God.
Catholic doctrine is a little different, as it sees a continuation of the Aaronic priesthood in the "ministerial" (ordained) priesthood. Although many people have things to say against him, I have Raymond Brown to thank for the fact that I realised early on - long before I became Catholic, while I was still a seminarian - that the inauguration of the new covenant in the Highpriesthood of Christ does not exclude the existence of a continuing order of priests within and serving the Priestly People of the Church. His little book "Priest and Bishop: Biblical Reflections" was most helpful in this regard. The Old Covenant People of God was a true priesthood embracing the whole nation of Israel, and yet Israel herself required a priesthood to serve her, to offer sacrifice and intercession for her, and to do all the things for her that Leithard outlines so well in his article. The New Covenant People of God are no different, and there is no more contradiction in having an order of ministerial priests within the priestly community in the New Covenant than there was in the Old Covenant. We, as with the Lutherans, see the Priesthood of Christ as the final fulfillment of both the Aaronic priesthood and the priesthood of Israel, but we say that both the continuing New Testament office of the ministry AND the continuing New Testament priestly community of all the faithful derive from this one Priesthood of Christ.
Where Leithard has it exactly correct is his criticism of the way in which the rise of Individualism has skewed the teaching of the baptismal ministry, to lead to the notion that the idea of the priesthood of the baptised somehow leads to the detachment of the individual from the liturgical assembly. Perhaps he could have taken this a little further and noted that the true New Testament doctrine about "the priesthood of all believers"/"common baptismal priesthood" teaches a priesthood that each of the baptised possesses only in union with the whole community of the Church. It is only AS "the People of God" that we exercise this priesthood.
This is then not unrelated to the doctrine that we often hear from Protestants in criticism of our Catholic practice of canonising particular individual believers as "saints". They object that "we are all saints". Yes, but not individually. Whenever the New Testament refers to "the saints" they are speaking of the whole Church as one body of the sanctified, not of a property that each believer already in this life possesses in and of ourselves in some individual manner.
Catholics can affirm with Lutherans that all the baptised are together "priests" and all the baptised are together "saints", but we pay especial attention to the danger of individualism of which Leithard's short article warns us.