The most astonishing of these compilations, from the viewpoint of wealth of material and complexity of detail, is the work of Vincent of Beauvais (died c.1264), which groups the entire knowledge of the Middle Ages under three heads: "Speculum naturale", "Speculum doctrinale", and "Speculum historiale"; later an anonymous writer published, as a supplement, the "Speculum morale".The first attempt to compile an encyclopedia in the real sense of the word is evident in the "Etymologiæ sive origines" of Isidore of Seville (c.
It is the Church alone, "the pillar and ground of truth ", imbued with and directed by the Holy Spirit , that guarantees to her children through her infallible teaching the full and unadulterated revelation of God.
Consequently, it is the first duty of Catholics to adhere to what the Church proposes as the "proximate norm of faith " ( regula fidei proxima ), which, in reference to the Eucharist, is set forth in a particularly clear and detailed manner in Sessions XIII, XXI, and XXII of the Council of Trent.
What we do particularly discover is a new proof of the reasonableness of the Catholic religion, from the circumstance that Jesus Christ in a wonderfully condescending manner responds to the natural craving of the human heart after a food which nourishes unto immortality, a craving expressed in many pagan religions, by dispensing to mankind His own Flesh and Blood.
All that is beautiful, all that is true in the religions of nature, Christianity has appropriated to itself, and like a concave mirror has collected the dispersed and not infrequently distorted rays of truth into their common focus and again sent them forth resplendently in perfect beams of light.
The first to attempt a work founded on the philosophy and interrelation of sciences was Francis Bacon, Lord Verulam, in his incomplete "Instauratio Magna", the second part of which was the "Novum organum" (London, 1620), and his "De dignitate et augmentis scientiarum" (1623).
His immediate successors, however, who had not mastered their materials, did not rise above the old-fashioned compilation of dry facts suited only for general instruction or as works of reference for scholars, e.g.The modern science of comparative religion is striving, wherever it can, to discover in pagan religions "religio-historical parallels", corresponding to the theoretical and practical elements of Christianity, and thus by means of the former to give a natural explanation of the latter.Even were an analogy discernible between the Eucharistic repast and the ambrosia and nectar of the ancient Greek gods, or the haoma of the Iranians, or the soma of the ancient Hindus, we should nevertheless be very cautious not to stretch a mere analogy to a parallelism strictly so called, since the Christian Eucharist has nothing at all in common with these pagan foods, whose origin is to be found in the crassest idol- and nature-worship.The organic connection of this mysterious triad is clearly discerned, if we consider Divine grace under the aspect of a personal communication of God.Thus in the bosom of the Blessed Trinity, God the Father, by virtue of the eternal generation, communicates His Divine Nature to God the Son, "the only begotten Son who is in the bosom of the Father" ( John ), while the Son of God, by virtue of the hypostatic union, communicates in turn the Divine Nature received from His Father to His human nature formed in the womb of the Virgin Mary ( John ), in order that thus as God-man, hidden under the Eucharistic Species, He might deliver Himself to His Church, who, as a tender mother, mystically cares for and nurtures in her own bosom this, her greatest treasure, and daily places it before her children as the spiritual food of their souls.The expression " Blessed Sacrament of the Altar", introduced by Augustine, is at the present day almost entirely restricted to catechetical and popular treatises.