2. It is the precise paraphrase of the learned bishop’s chapter on the Holy Spirit. Thus he begins the chapter with an assertion of the procession of the Holy Spirit from both the Father and the Son. He then calls this Spirit _donum Dei_, and several times repeats the phrase. He argues that the Spirit is coequal and coeternal God. He then discusses the term _Paraclete_, and proceeds to speak of the _septiformis_ nature of His power. Next follows a most significant and unusual expression—namely, that the Holy Spirit is _digitus Dei_—the finger of God. And the consecution and coincidence of thought is still further increased by an allusion to the grace which bestowed the gift of tongues. He then speaks of the Spirit as fire—which accords with the word _accende_—and then he explains the simile of water, which corresponds with the word _infunde_ and with the previous phrase _fons vivus_. He also quotes from the Gospel of John to show that this “living water” means no more nor less than the Holy Spirit. These coincidences are doubly remarkable, for they not only exhibit the same ideas—some of which, by the way, are quite uncommon—but they also set them forth in the precise order in which the good bishop employs them in his hymn. It is as if, being aroused and animated by his great and noble theme, he had turned to verse as an appropriate medium of lofty praise and had sung from his heart this immortal hymn. 3. To these reasons we may add a third—that the internal structure of the hymn shows its author to have been a person of theological soundness, spiritual insight, scriptural knowledge, genuine scholarship, and a natural poetical capacity. These facts again agree with what we know to have been the talents and learning of Rabanus Maurus. 4. If Gregory had written this hymn it would have appeared at an earlier date and would have been undoubtedly attributed to its illustrious author; whereas it is not in his carefully compiled writings nor is it accredited to him by Thomasius or any hymnologist before the time of Mone and Wackernagel. 5. Charles the Great had not the learning, and both he and his grandson, Charles “the Bald,” are named on the strength of a long-exploded and always anachronistic tradition. 6. Ambrose is out of the question by the theological limitation of the stanza _Per te sciamus_, etc. 7. Finally, we have the right to believe that a man whose other hymns have been so extensively, though anonymously, introduced into the worship of the Church, was entirely competent to frame this present hymn.