Fine.I would be most interested to see that notation. Someone posted a reference to canon law, but, it did not specify that it was a liturgical day.
**Can. 202 §1. In law, a day is understood as a period consisting of 24 continuous hours and begins at midnight unless other provision is expressly made
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I think it has been beaten to death already that there is no “two-for-one” deal and that everyone agrees with it.Furthermore, there is no such thing as a two-for-one deal when it comes to fulfilling the obligation. For example, when Christmas Eve falls on a Sunday, the evening Mass on that day only satisfies the Christmas obligation, not the Sunday obligation.
This is a common misconception. The readings have nothing to do with the obligation. The important thing is that one attends Mass. This is allowable because Canon Law states that attendance at Mass or Divine Liturgy at any Catholic rite the evening before satisfies the obligation (Can. 1248). Other than that, Canon Law says nothing about the nature or the readings of the Mass. What one must do is attend Mass.In order to fulfill the obligation, the readings must be from the propers of that day. Therefore, you fulfill your obligation on Saturday evening, for the fourth Sunday of Advent up until before the vigil Mass for Christmas Eve, Sunday evening.
Therefore, if one fails to attend the Fourth Sunday of Advent Mass in the Daytime, but attends the Christmas Eve Mass in the evening of Dec 24, then attends Mass AGAIN on the 25th, both the Fourth Sunday and Christmas obligations are fulfilled.
The same thing works this year for the Immaculate Conception. If one attends Mass on Saturday evening Dec. 8 and it happens to be the vigil Mass for Sunday, you will have the Sunday readings. **But ***this satisfies the obligation for the Immaculate Conception, December 8. It does NOT satisfy the Sunday obligation. *You will have to go to Mass again on Sunday, Dec. 9 to satisfy your Sunday obligation. The readings will be the same.