'Priests (...) by the power of the sacrament of orders, in the image of Christ the eternal high Priest, are consecrated to preach the Gospel and shepherd the faithful and to celebrate divine worship, so that they are true priests of the New Testament (...) They exercise their sacred function especially in the eucharistic worship or the celebration of the Mass by which, acting in the person of Christ and proclaiming His Mystery, they unite the prayers of the faithful with the sacrifice of their Head and renew and apply in the sacrifice of the Mass, until the coming of the Lord, the only sacrifice of the New Testament namely that of Christ offering Himself once for all as a spotless Victim to the Father.' (Lumen Gentium, 28). The idea of acting 'in persona Christi' is an important theological concept developed further and pondered upon in this valuable collection of essays. The question of priesthood is discussed by a pool of acclaimed scholars and analyzed from biblical, patristic, systematic, historical and canonical points of views. The input made during the Seventh Fota International Liturgical Conference is an important contribution to the ongoing debate about the character and essential identity of the ordained priesthood.