Canon XII.
Canons of Local Councils Received Ecumenically (Ancyra, Gangra, Neocaesarea, Antioch, Laodicea) · The Seven Holy Ecumenical Councils
If any one, under pretence of asceticism, should wear a peribolæum and, as if this gave him righteousness, shall despise those who with piety wear the berus and use other common and customary dress, let him be anathema.
LocalE 3.15.2
The βήροι (lacernæ) were the common upper garments worn by men over the tunic; but the περιβόλαια were rough mantles worn by philosophers to show their contempt for all luxury. Socrates (H. E., ii. 43) and the Synodal Letter of Gangra in its third article say that Eustathius of Sebaste wore the philosopher’s mantle. But this canon in no way absolutely rejects a special dress for monks, for it is not the distinctive dress but the proud and superstitious over-estimation of its worth which the Synod here blames.
LocalE 3.15.7