Sabbatians
From BiblePortal Wikipedia
Sabbatians [1]
a Judaizing section of the Novatians, who owed their origin to Sabbatius, a presbyter that had been ordained by Marcian (Socrat. Hist. Eccl. 5, 20; 7, 15). They assumed the name of Protopaschites, and refused to communicate with any but those who adopted with them the Quartodeciman rule in regard to the paschal festival. The Sabbatians were included among heretics who were condemned in A.D. 381 by the seventh canon of the Council of Constantinople (Mansi Concil. 3, 563).