If you attend the service conducted in Latin in the Tridentine rite by a priest of the Society of St. Pius X, would you have fulfilled your Sunday Mass obligation?
According to Zabrina Decker, vice chancellor of the Archdiocese of Milwaukee, the answer is no.
According to a Letter by Msgr. Camille Perl Regarding Society of St. Pius X Masses, it's not recommended, and "If your primary reason for attending were to manifest your desire to separate yourself from communion with the Roman Pontiff and those in communion with him, it would be a sin", but the answer is yes.
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