[Question:]{.underline} Can a Roman Catholic satisfy his Sunday obligation by attending an Eastern rite Mass?
[Answer:]{.underline} The Church’s discipline on this question has changed over time. There was a time when every Catholic was bound to assist at Mass in his parish church. This law was already abrogated in the 16^th^ century, when the Popes permitted the assistance at Mass in Franciscan and Dominican convents. Benedict XIV taught in the 18^th^ century that bishops could no longer bind their faithful to assist at Mass in the parish churches, for the contrary custom was already established. The growth of Eastern rite Catholic churches throughout the 19^th^ century brought to a head the question of whether Latin rite Catholics could assist at Mass in eastern rite Churches and vice versa, which was resolved in the 1917 Code of Canon Law.
Canon 1249 has this to say: “The precept of hearing Mass is fulfilled by being present at Mass celebrated [in any Catholic rite]{.underline}, either in the open, or in any church or public or semipublic oratory…”. There is no difficulty in interpreting these very clear words. Bouscaren & Ellis (Canon Law) has this commentary to make: “The Mass may be celebrated in any Catholic rite; therefore an Oriental may satisfy the precept by hearing Mass according to the Latin rite, and a Latin by hearing it according to any of the Catholic Oriental rites” (p. 635). Canon 1248 of the 1983 Code reiterates the same law: “The precept of participating in Mass is satisfied wherever it is celebrated in a Catholic rite…”
Consequently, it is quite clear that those who attend the Liturgies in the schismatic Orthodox churches who are not united with Rome, do not satisfy their Sunday obligation, whereas those who attend the same liturgies celebrated by Uniate Eastern rite Catholics certainly do. This includes such rites as the Ukrainian, Greek Catholic and Maronite rites. However, it does not mean that it is prudent to attend such rites. For the rites of these uniate Eastern rite Catholics have, alas, also been modified in the spirit of Vatican II, and the priests have been taught the revolutionary, humanistic theology of the post-conciliar church. Consequently, it would be very imprudent to assist at such rites unless one had the guarantee that they were being celebrated in the traditional way, in the traditional liturgical language (such as Old Slavonic) by traditional priests, who are in communion with Rome, such as the priests of the Society of Saint Josaphat in the Ukraine.
Answered by Father Peter Scott, SSPX.