The De vetere et novo testamento quaestiones which Faustino Arévalo, S.J. (d. 1824), the illustrious editor of St. Isidore of Seville, regarded as authentic has long been recognized as spurious. In fact it can be considered one of the oldest extant pseudo-Isidorian works. In identifying this curious little catechetical work and publishing the editio princeps, Arévalo was convinced that he had rightly contributed to the list of the accepted works of St. Isidore. Indeed, he believed that the historical testimony of both St. Braulio and St. Ildefonsus, if rightly interpreted, favored the authenticity of this work and its inclusion under the title, Secretorum expositiones sacramentorum. The evidence which he presented in favor of the acceptance of this ancient catechism is reducible to three general headings: the antiquity of the manuscript in which this work has come down to us, the absence of positive reasons negating authenticity, and the presence of evidence affirming it. Under the latter heading he adduced various extrinsic authority, e.g., that of Gratian and Grialius, which is of no decisive importance in settling this question; and he stressed the inner dependence of the text of the quaestiones on the works of St. Isidore — a literary dependence which in the Early Middle Ages is normal enough in works of this character and which certainly is not a definitive norm for deciding the genuineness of Isidorian works.