E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Also called Pseudo or False Decretals. A spurious compilation of fifty-nine decretals by Mentz, who lived in the ninth century, and fraudulently ascribed them to Isidore of Seville, who died in the sixth century. Prior to the ninth century the only authentic collection of decretals or letters of the popes in reply to questions proposed to them by bishops, ecclesiastical judges, and others, was that of Dionysius the Little [Exiguus], a Roman monk, who lived in the middle of the sixth century. He commences with Pope Siricius (fourth century). The Isidorian decretals contain fifty-nine letters ascribed to persons living between Clement and Siricius, and forty others not contained in the Dionysian collection. The object of these forged letters is either to exalt the Papacy or enforce some law assuming the existence of such exaltation. Amongst these spurious letters are the decretal of St. Anacletus, the decretal of St. Alexander, the letter of Julius to the Easterns, the synodical letter of St. Athanasius, the decretal of St. Fabian instituting the rite of the chrism, and so on.
La réforme pseudo-Isidorienne, adoptée par S. Nicholas, en 865, par le huitième concile cumenique en 870, confirmé par le concile de Trent en 1564, elle est depuis neuf siecles le droit commun dans léglise catholique . ce quil est impossible de justifler et même dexcuser, cest le moyen employé par le pseudo-Isidore pour arriver à ses fins.Etudes Religieuses, No. 47, p. 392.