What is “the evening of the previous day”? Despite the view of some commentators that this should be interpreted as beginning only at 1400 hours (2 PM) on that day, it is the firm view of this commentary that the evening of the previous day begins at midday (12 noon) on that day itself. In some dioceses there is a local regulation to the effect that the so-called vigil or anticipated Mass may not be celebrated before, say 5 or 6 PM… Those regulations do not in any way concern the time prescribed for fulfilling the obligation to assist at Mass: thus e.g. if in such a diocese a person were to attend a nuptial Mass in the early afternoon on Saturday, that person would have fulfilled the obligation … of this canon [1248] (The Canon Law: Letter & Spirit, Canon Law Society of Great Britain and Ireland, 1995).