Walter Alison Phillips

“ Mitres are the distinctive headdress of bishops; but the right to wear them, as in the case of the other episcopal insignia, is granted by the popes to other dignitaries—such as abbots or the heads and sometimes all the members of the chapters of cathedral or collegiate churches. In the case of these latter, however, the mitre is worn only in the church to which the privilege is attached and on certain high festivals. Bishops alone, including of course the pope and his cardinals, are entitled to wear the pretiosa and auriphrygiata; the others wear the mitra simplex. ”

“ At general councils bishops wear white linen mitres, cardinals mitres of white silk damask; this is also the case when bishops and cardinals in pontificalibus assist at a solemn pontifical function presided over by the pope.
Lastly, the mitre, though a liturgical vestment, differs from the others in that it is never worn when the bishop addresses the Almighty in prayer—e.g. during mass he takes it off when he turns to the altar, placing it on his head again when he turns to address the people (see 1 Cor. xi. 4) . ”

“ Surmounting all, at the intersection of the arches is a cross. In Russia this usually lies flat, only certain metropolitans, and by prescription the bishops of the eparchy of Kiev, having the right to have the cross upright (see fig. 2) . In the Armenian Church priests and archdeacons, as well as the bishops, wear a mitre. That of the bishops is of the Latin form, a custom dating from a grant of Pope Innocent III.; that of the priests, the sagvahart, is not unlike the Greek mitre (see fig. 3) . In the Syrian Church only the patriarch wears a mitre, which resembles that of the Greeks. ”