Christians have from the beginning believed God to be the author of the Holy Scriptures. The Fathers of the fourth Council of Carthage, in the profession of faith required of the new bishops, expressly made mention of this truth. The same profession of faith is made in our day by those who are promoted to the episcopate. Pope S. Leo IX., in the profession of faith to which he required Peter of Antioch to subscribe, declared God to be the author of the Old and New Testaments, including the law, the prophets, and the apostolic books. The Council of Florence inserted this same article in the decree about the Jacobites: The most holy Roman Church “confesses that it is one and the same God who is the author of the Old and the New Testament; that is to say, the law, the prophets, and the Gospel; the saints of both Testaments having spoken under the inspiration of the same Holy Spirit.” Finally, the Council of Trent, renewing the decree of Florence, accepted all the canonical books of the two Testaments, God being the author of them both: _Cum utriusque unus Deus sit auctor_. Besides, all these decrees were only an expansion of the words of the Nicene Creed: _Qui locutus est per prophetas_. The Catholic dogma is explicit: “God is the author of the books of the Old and the New Testament.” The definitions of the ancient councils had for their direct object the condemnation of the errors of the Manichees, who made a distinction between the two Testaments, attributing the first to the evil principle, the second to the true God. But, secondarily, these definitions, referring to the actual origin of the Holy Scriptures, declare they have God for their author. The Council of Florence gave this explanation: “Because the saints of both Testaments wrote under the inspiration of the same Holy Spirit.” But what is meant by inspiration? An important question, on which not only Protestants differ from Catholics, but on which even orthodox writers are not agreed.