The Eucharist is the ritual, sacramental action of thanksgiving to God which is the principle Christian liturgical celebration of and communion in the passion, death and resurrection of Christ. The liturgical action called the Eucharist is also traditionally known as the Holy Sacrifice of the Mass. It is one of the seven sacraments of the Church. The Holy Eucharist completes Christian initation. The celebration of the Eucharist is at the heart of the Church's life.