What is the difference between a liturgist and a liturgiologist? This is an important question because the answer has an impact on how we approach participation in the Mass. A liturgist is one who offers public worship of God. The Church teaches that Christ is the Supreme Liturgist, offering himself entirely to the Father. The Constitution on the Sacred Liturgy insists that Christ himself is the priest. The Liturgy is the action of Christ and of his Body, the Church. Following the pattern of Christ, then, the liturgist is the one who actually prays at Mass.