Paprocki, the chairman of the USCCB’s Committee on Canonical Affairs and Church Governance, had in July written to the Holy See seeking clarification on whether an obligation transfers when the feast itself is transferred.

Archbishop Filippo Iannone, the prefect of the legislative text dicastery, told Paprocki that “the feast must be observed as a day of obligation on the day to which it is transferred.” 

Iannone noted in the letter that certain feast days are established by canon law as days of obligation. These “must be observed” and “the canon does not provide exceptions,” he noted in the letter.

Iannone clarified that if someone is unable to attend Mass for a “grave cause” such as illness or caring for an infant, then they are excused, as “no one is bound to the impossible.” 

Several U.S. dioceses are already stipulating that Mass attendance is obligatory on that day. The Archdiocese of Boston lists the day as obligatory on its website. The Archdiocese of Cincinnati website cited the Vatican’s clarification in making the announcement.

The Diocese of Youngstown, Ohio, also cited the Vatican’s clarification that the obligation transfers with the feast day. 

Multiple other archdioceses confirmed to CNA that the day would be treated as obligatory, including Portland, Oregon; Las Vegas; Miami; Atlanta; St. Louis; Denver; Oklahoma City; and Seattle.

Cardinal Daniel DiNardo of the Archdiocese of Galveston-Houston, meanwhile, granted a dispensation for the feast day given the “short notice” of the change. 

DiNardo noted that “many parishes and families already have in place the schedules for Advent and Christmas, and that this will cause confusion due to the short notice of this change.”

He urged the faithful, however, to “make a special effort to attend Mass on Dec. 9 even though there is no obligation to do so this year.”