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Saint Charles laid down regulations about the dimensions of vestments for the Sacred Liturgy because, it would seem, he was concerned that the form of the vestments, which had been handed down for centuries, was being cast aside in favour of something convenient and “fashionable”. The chasuble, derived from the Latin word for “a little house” had been for centuries an ample garment. In the 15th and 16th centuries, there had been significant divergence from this Tradition, however, resulting in a form of chasuble that wasn’t ample, but cut right back so that it comprised a sort of narrow pendant, front and back, on the wearer. We know this form of chasuble as the “Roman” or “fiddleback” chasuble, and some claim that this is the form of the chasuble that is truly “traditional”. But Borromeo didn’t think that: he thought it represented a break with Tradition. And he specified the minimum size to which he expected chasubles to conform.
They were to be at least 54 inches (138cm) wide and, at the back, they were to reach down almost to the heels of the wearer. Saint Charles wasn't attempting to determine how a chasuble should be decorated, he was simply trying to preserve a minimum standard for the dimensions of the chasuble.
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As a vestment-maker, I am blessed to receive frequent enquiries from newly-ordained priests and deacons and more often than not, they are interested in obtaining that style of vestment used by S' Charles Borromeo and S' Philip Neri. Happily, these young men are not interested in partisan views of various commentators about the revival of interest in such vestments.
A greeting on the Feast of Saint Charles to all priest-customers of the Saint Bede Studio.