If I am late for Mass, at what point have I failed to fulfil the Sunday Mass obligation? For example if I miss the Gospel, have I missed Mass?
In older manuals of moral theology, this subject was discussed extensively. In the first place, it was always stated, and remains the case today, that Catholics are under obligation to attend the whole of Mass on days of precept. The answer to the question “When am I late for Mass?” is the same then as now: “If you arrive after it has started.”
The secondary question that was asked by the manualists, and considered at length, was what omission would constitute a mortal sin rather than a venial sin. Briefly, the answer is that it is grievous matter to miss a part of the Mass that is notable either because of its length or its importance. I would rather not go into the calculation of what is “notable” because we should regard all of the parts of the Mass as important, rather than trying to rank them so that we only commit a venial sin. Nevertheless, if someone were to miss the whole of the Liturgy of the Word, they would not fulfil the obligation of attending Mass and should go to another Mass if possible unless there is a reasonable excusing cause.
A further consideration is that nowadays, most people who attend Mass receive Holy Communion. This requires something more of us than simply fulfilling the obligation of attending Mass. It is true that devout participation in the liturgy of the Mass itself is a good preparation for Holy Communion but we should also make some special preparation and thanksgiving for Holy Communion in addition to the brief opportunities provided during the course of the Mass.
Such preparation can be made at home, but this may be difficult in a busy household. It is a good practice to try to arrive at least a few minutes before Mass, and to stay for a while afterwards to give ourselves space for some private prayer to enrich our participation in the Mass and our devotion at Holy Communion.
Catholic Dilemmas column published in the Catholic Herald
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