TRANSUSTANZIAZIONE. – Etymologically (Lat. trans = beyond, substantia = substance), it denotes the passage of one substance into another. It is from the thirteenth century that the Church’s official expression dates for indicating the manner in which the real presence of the Body and Blood of Jesus Christ in the Eucharist is effected, namely, the wondrous and singular conversion of the whole substance of the bread into the Body and of the whole substance of the wine into the Blood of Jesus Christ, with only the appearances of the bread and wine remaining unchanged (Council of Trent, sess. XIII, can. 2; Denz-U, 884).
This doctrine, implicit in Jesus’ words « This is my Body » and « This is my Blood », was gradually formulated, in equivalent terms, by the Fathers (transmutation, transformation, transelementation, etc.; V. EUCARISTIA, III, col. 764), by the ecclesiastical authors of the Carolingian period (cf. C. Gliozzo, La dottrina della conversione eucaristica in Pascasio Radberto e Ratrammo manaci di Corbia, Palermo 1945), and by the Lateran Synod of 1079 against Berengar of Tours (substantialiter converti: Denz-U, 355; cf. A. Lentini, Alberico di Montecassino nel quadro della Riforma gregoriana, in Studi
Gregoriani, IV, Roma 1952, pp. 55-109, spec. p. 66), until, in the twelfth century, the felicitous expression transubstantiatio was introduced, and was received in the official documents of the Church from the Fourth Lateran Council (1215) to the Council of Trent (Denz-U. 430, 465, 581, 698, 884).
It was held that the first to use the word transubstantiare had been the bishop of Autun, Stefano di Beaugé (d. in 1139 or 1140), in the Tractatus de Sacramento Altaris, chap. 13: « Oramus ut cibus hominum fiat cibus Angelorum, scilicet ut oblatio panis et vini transubstantietur in Corpus et Sanguinem Jesu Christi » (PL. 172, 1291); but Fr. D. Van den Eynde demonstrated (Le tractatus de Sacramento Altaris faussement attribué à Etienne de Beaugé, in Recherches de théologie anc. et méd., 19 [1952], pp. 225-43) that this work is not by Stefano di Beaugé but by an author of the second half of the twelfth century (perhaps the other Stefano, who was bishop of Autun from approximately 1170 to 1189); the first established testimony to this term therefore remains the passage written around 1150 by Rolando Bandinelli (later Pope Alessandro III): « Verumtamen, si necessitate imminente, sub alterius panis specie consecraretur, profecto fieret transubstantiatio, Sanguinis autem numquam fit nisi de vino transubstantiatio » (Sententiae, ed. U. Gietl, Friburgo in Br. 1891, p. 231). Subsequent testimonies are numerous (cf. J. De Ghellinck, L'Eucharistie au XIIe siècle en Occident, in DThC, V. coll. 1287-1302). This term, rejected by Luther and by all Protestants, but declared by the Council of Trent to be an « aptissima » expression of Catholic dogma, was much debated within orthodox doctrine (v. EUCARISTIA, III, coll. 764-66); yet its value and precise meaning were never called into question until recent years, when an attempt was made to empty it of its real content by appealing to the concept of a total transformation, not in a substantial sense but purely within the sphere of significations (symbolic theory). The error was identified and rejected by Pius XII in the encyclical Humani generis, 12 August 1950 (cf. A. Piolanti, De symbolismo et ubiquismo eucharistico a Pio XII proscripto, in Euntes docete, 4 [1951], pp. 56-71).