Chasuble (Lat. casula, casubula, and casibula; also panula, plancta; Gr. phelonion or phainolēs), the uppermost garment worn by priests in the Eastern and the Roman Catholic Church when robed for the celebration of the mass; having been at first a secular garment of ceremony common to both sexes. When adopted as an ecclesiastical robe, it was for some centuries used by all grades of the clergy, even as low as that of the acolytes, and its earliest restriction to priests appears in Canon xxviii. of the Fourth Council of Toledo, in 633 A.D. It was called also 'the Vestment,' though this term more properly denotes collectively all the robes worn at mass, of which the chasuble is the principal item. Originally it cov- ered the priest from head to foot, like a little house, whence some writers think it had its name of casula (Isid. Hispal., Orig. xix. 24).
The earliest direct evidence for it as a sacerdotal robe is in the mosaics of San Vitale at Ravenna (547 A.D.), where Archbishop Maximian is depicted wearing it. Rich materials, cloth of gold or silver, silk, and velvet, elaborately embroidered, were used for it. In the middle ages it was of an elliptical shape, like a vesica piscis, with a hole in the middle for the head; it had no sleeves. When put on it showed two peaks, one hanging down before; another, on which a cross was embroidered, hanging down behind, though in Italy the cross was and is usually in front. The Greek chasuble is ampler and rounder than the Latin form, having more the nature of a mantle, and the episcopal chasuble is provided with a pattern of crosses. Archbishops do not wear the chasuble, but another vestment named Sakkos, which is worn by bishops also in Russia. The modern Latin form is commonly a parallelogram with rounded angles, or else resembles a violin. In the Reformed Church of England the chasuble was enjoined as the celebrant's robe at Holy Communion by the Prayer-book of 1549, prohibited by that of 1552, but again legalised in 1559. It remained, however, in practical abeyance (its place in cathedrals and on solemn occasions being supplied by the cope) till recent times, when its use has been partially revived, first in 1851 at St Thomas the Martyr in Oxford. In France the press or wardrobe in which chasubles were kept was called the chasublier.