"Christ is always present in his Church, especially in her liturgical celebrations. He is present in the sacrifice of the Mass, not only in the person of his minister, 'the same now offering, through the ministry of priests, who formerly offered himself on the cross,' but especially under the Eucharistic species. By his power he is present in the sacraments, so that when a man baptizes it is really Christ himself who baptizes. He is present in his Word, since it is he himself who speaks when the holy Scriptures are read in the Church. He is present, lastly, when the Church prays and sings, for he promised: 'Where two or three are gathered together in my nmae, there am I in the midst of them.'"
(Sacrosanctum concilium, n. 7)