The Biblical Canon of
Augustine of Hippo

Saint Augustine (354-430) is generally recognized as the most important theologian in the Western church after the New Testament.  He published many significant biblical commentaries and theological works, and many of his sermons have been preserved.  In 396, he began composing On Christian Teaching (De Doctrina Christiana), which was an essay on biblical interpretation.  In the early portion of this work, Augustine included a list of books in the biblical canon.  Augustine included all of the books of the canon later approved by the Council of Trent -thus including the Deuterocanonical books- except that Augustine did not name explicitly Lamentations, Baruch, or the Epistle of Jeremiah, but it is likely that he included all of these books under the title Jeremiah.  Augustine makes no distinctions between the Jewish canon and the Deuterocanonicals and does not group them separately, but rather mixes them with the other books.  His New Testament canon mirrors that of Athanasius.

Now, in regard to the canonical scriptures, he must follow the judgment of the greater number of Catholic churches; and among these, of course, a high place must be given to such as have been thought worthy to be the seat of an apostle and to receive epistles. Accordingly, among the canonical scriptures he will judge according to the following standard: to prefer those that are received by all the Catholic churches to those which some do not receive. Among those, again, which are not received by all, he will prefer such as have the sanction of the greater number and those of greater authority, to such as are held by the smaller number and those of less authorit.  If, however, he shall find that some books are held by the greater number of churches, and others by the churches of greater authority (though this is not a very likely thing to happen), I think that in such a case the authority on the two sides is to be looked upon as equal.”  (On Christian Doctrine, Book 2; 12).

The above quote illustrates how Augustine viewed the canon of Scripture; it was the Church with the authority of the apostles, which had been handed on via the succession of bishops, that rightly determined the canon of the Bible.

Now the whole canon of Scripture on which we say this judgment is to be exercised, is contained in the following books: five books of Moses, that is, Genesis, Exodus, Leviticus, Numbers, Deuteronomy; Joshua; Judges; Ruth; four books of Kings, and two of Chronicles] ... The books now mentioned are history, which contains a connected narrative of the times, and follows the order of the events. There are other books which seem to follow no regular order, and are connected neither with the order of the preceding books nor with one another, such as [Job, Tobias, Esther, Judith, two books of Maccabees, and the two of Ezra]. . . . Next are the prophets, in which there is one book of the psalms of David; and three books of Solomon, viz., Proverbs, Song of Solomon, and Ecclesiastes. For two books, one called Wisdom and the other Ecclesiasticus, are ascribed to Solomon from a certain resemblance of style, but the most likely opinion is that they were written by Jesus the son of Sirach. Still they are to be reckoned among the prophetical books, since they have attained recognition as being authoritative. The remainder are the books which are strictly called the prophets … (Hosea, Joel, Amos, Obadiah, Jonah, Micah, Nahum, Habakkuk Zephani-ah, Haggai, Zechariah, Malachi; then there are the four greater prophets, Isaiah, Jeremiah, Daniel, Ezekiel]. The authority of the Old Testament is contained within the limits of these forty-four books.” (On Christian Doctrine, Book 2; 13)

Sources: 

• Edmon L. Gallagher and John D. Meade. The Biblical Canon Lists from Early Christianity:  Texts and Analysis.  Oxford University Press. 2017