I should mention that this entire introductory section, GIRM 1-15, is an addition from the earlier editions released in the last century. As we continue through this introduction, we have an important reminder about the priesthood of believers. One might consider that the conciliar document Sacrosanctum Concilium is largely a work treating the priesthood of believers, especially given the connection of the faithful to God, and that our sanctification is realized, in part, through our cooperation with Christ’s presence and activity within Christian worship.
5. Moreover, by this nature of the ministerial Priesthood, something else is put in its proper light, something certainly to be held in great esteem, namely, the royal Priesthood of the faithful, whose spiritual sacrifice is brought to completion through the ministry of the Bishop and the Priests, in union with the Sacrifice of Christ, the sole Mediator. For the celebration of the Eucharist is the action of the whole Church, and in it each one should carry out solely but totally that which pertains to him, in virtue of the place of each within the People of God. The result of this is that greater consideration is also given to some aspects of the celebration that have sometimes been accorded less attention in the course of the centuries. For this people is the People of God, purchased by Christ’s Blood, gathered together by the Lord, nourished by his word, the people called to present to God the prayers of the entire human family, a people that gives thanks in Christ for the mystery of salvation by offering his Sacrifice, a people, finally, that is brought together in unity by Communion in the Body and Blood of Christ. This people, though holy in its origin, nevertheless grows constantly in holiness by conscious, active, and fruitful participation in the mystery of the Eucharist.
 Cf. Second Ecumenical Council of the Vatican, Decree on the Ministry and Life of Priests, Presbyterorum ordinis, no. 2.
 Cf. Second Ecumenical Council of the Vatican, Constitution on the Sacred Liturgy, Sacrosanctum Concilium, no. 11.
One definition of a priest is a person who conducts religious rituals on behalf of others. In its essence, Catholic liturgy involves an active assembly, as SC 11 is cited here. This action includes the quality of being able to respond to grace, and indeed, to be able to pray for and on behalf of the world. Intercessory prayer is integral to our worship tradition, and shouldn’t be minimized.
It’s important to note that this priesthood is not based on any human factor of participation or personal accomplishment. The liturgy involves a progression, as noted above. God’s agency gathers us. God’s revelation of the Divine Self nourishes us. In response, we bring the prayers of others, we offer sacrifice, and we assent to the unity expressed in the Sacrament.
When you think about it, the priesthood of the faithful is a pretty radical concept. Maybe that’s why so many Catholics have such difficulty with it. What about you: any comments on this?