1. Term and concept. Etymologically, the word “symbol” comes from certain usages in ancient law. Two parts of a ring, staff or tablet served, when they were brought together συμ-βάλλειν, to identify legitimate guests (tessera hospitalitatis), messengers and partners. Thus the word came to have the meaning of “treaty”, and in ecclesiastical language could designate the common profession of faith, the fixed and obligatory formulas or creeds (the “symbols”) and then the instruments, images and acts in which the faith was expressed. …