CIC 2180 The precept of the Church specifies the law of the Lord more precisely: “On Sundays and other holy days of obligation the faithful are bound to participate in the Mass.”1 “The precept of participating in the Mass is satisfied by assistance at a Mass which is celebrated anywhere in a Catholic rite either on the holy day or on the evening of the preceding day.”2

1 CIC, can. 1247.
2 CIC, can. 1248 # 1.