"Accordingly, just as Christ was sent by the Father so also he sent the apostles, filled with the Holy Spirit. This he did so that they might preach the Gospel to every creature and proclaim that the Son of God by his death and resurrection had freed us from the power of Satan and from death and brought us into the Kingdom of his Father. But he also willed that the work of salvation which they preached should be set in train through the sacrifice and sacraments, around which the entire liturgical life revolves."
Source: Catechism of the Catholic Church (Vatican.va)