The sad reality of the history of the Church in North Africa after Augustine died in 430: The effects of the Donatist Controversy and the Vandal Barbarian Invasions, who were Arian in their theology.
This is an excellent summary of some of Augustine’s statements on the priority of Scripture above the church against the Donatists, from Augustine’s work, “On the Unity of the Church” ( De Unitate Ecclesiae), which has never been fully translated into English and is not part of the standard Early Church Fathers book sets.
Addendum: (Oct. 20, 2016)
Augustine's "On the Unity of the Church" has been recently fully translated into English.
Credit goes to David T. King for putting them in a com-box a while back at “Green Baggins” blog. (scroll up to comment # 136 - I have not learned how to get it exact yet. )
They are provided here without the original Latin text, but Pastor King has the Latin text with it at his posting. I am fairly certain that all of these are in the three volume set, Holy Scripture: The Ground and Pillar of Our Faith, by David King and William Webster. (also highlighted at the side bar of this web site.) Most of these are also quoted in James White’s excellent book, Scripture Alone.
This demonstrates the truth of the often quoted statement by B. B. Warfield, “For the Reformation, inwardly considered, was just the ultimate triumph of Augustine's doctrine of grace over Augustine's doctrine of the Church. “ (Warfield, Calvin and Augustine, p. 321-322)
·comment # 136
D. T. King said,
Augustine (354-430): Let us not hear, You [i.e., the Donatists] say this, I say that; but let us hear Thus saith the Lord. There are the Dominical books, whose authority we both acknowledge, we both yield to, we both obey; there let us seek the Church, there let us discuss the question between us. For trans., see William Goode, The Divine Rule of Faith and Practice, 2nd ed., (London: John Henry Jackson, 1853), Vol. 3, p 164. De Unitate Ecclesiae, Caput III, §5, PL 43:394.
Augustine (354-430): Therefore let those testimonies which we mutually bring against each other, from any other quarter than the divine canonical books, be put out of sight. For trans., see William Goode, The Divine Rule of Faith and Practice, 2nd ed., (London: John Henry Jackson, 1853), Vol. 3, p. 164. De Unitate Ecclesiae, Caput III, §5, PL 43:395.
Augustine (354-430): I would not have the holy Church demonstrated by human testimonies, but by divine oracles. For trans., see William Goode, The Divine Rule of Faith and Practice, 2nd ed., (London: John Henry Jackson, 1853), Vol. 3, pp. 164-165. De Unitate Ecclesiae, Caput III, §6, PL 43:395.
Augustine (354-430): Whoever dissents from the sacred Scriptures, even if they are found in all places in which the church is designated, are not the church. De Unitate Ecclesiae, Caput IV, §7, PL 43:395-396.
For trans., See Francis Turretin, Institutes of Elenctic Theology, 3 Vols., trans. George Musgrave Giger and ed. James T. Dennison (Phillipsburg: reprinted by Presbyterian and Reformed Publishing Co., 1992), Vol. 3, pp. 109-110.
Augustine (354-430): We adhere to this Church; against those divine declarations we admit no human cavils. For trans., see William Goode, The Divine Rule of Faith and Practice, 2nd ed., (London: John Henry Jackson, 1853), Vol. 3, p. 165. De Unitate Ecclesiae, Caput XI, §28, PL 43:410.
Augustine (354-430): I have the most manifest voice of my pastor commending to me, and without any hesitation setting forth the church, I will impute it to myself, if I shall wish to be seduced by the words of men and to wander from his flock, which is the church itself, since he specially admonished me saying, “My sheep hear my voice and follow me”; listen to his voice clear and open and heard; who does not follow, how will he dare to call himself his sheep? Let no one say to me, What hath Donatus said, what hath Parmenian said, or Pontius, or any of them. For we must not allow even Catholic bishops, if at any time, perchance, they are in error, to hold any opinion contrary to the Canonical Scriptures of God. Francis Turretin, Institutes of Elenctic Theology, trans. George Musgrave Giger, ed. James T. Dennison, Jr., (Phillipsburg: P&R Publishing, 1992),Vol. 3, pp. 91-92 and William Goode, The Divine Rule of Faith and Practice, 2nd ed., (London: John Henry Jackson, 1853), Vol. 3, p. 165. De Unitate Ecclesiae, Caput XI, §28, PL 43:410-411.
Augustine (354-430): All such matters, therefore, being put out of sight, let them show their Church, if they can; not in the discourses and reports of Africans, not in the councils of their own bishops, not in the writings of any controversialists, not in fallacious signs and miracles, for even against these we are rendered by the word of the Lord prepared and cautious, but in the ordinances of the Law, in the predictions of the Prophets, in the songs of the Psalms, in the words of the very Shepherd himself, in the preachings and labours of the Evangelists, that is, in all the canonical authorities of sacred books. Nor so as to collect together and rehearse those things that are spoken obscurely, or ambiguously, or figuratively, such as each can interpret as he likes, according to his own views. For such testimonies cannot be rightly understood and expounded, unless those things that are most clearly spoken are first held by a firm faith. For trans., see William Goode, The Divine Rule of Faith and Practice, 2nd ed., (London: John Henry Jackson, 1853), Vol. 3, p. 165. De Unitate Ecclesiae, Caput XVIII, §47, PL 43:427-428.
Augustine (354-430): We ought to find the Church, as the Head of the Church, in the Holy Canonical Scriptures, not to inquire for it in the various reports, and opinions, and deeds, and words, and visions of men. For trans., see William Goode, The Divine Rule of Faith and Practice, 2nd ed., (London: John Henry Jackson, 1853), Vol. 3, p. 165. De Unitate Ecclesiae, Caput XIX, §49, PL 43:429.
Augustine (354-430): For we do not say that we ought to be believed because we are in the Church of Christ, or because that Church to which we belong, was commended to us by Optatus, Ambrose, or other innumerable Bishops of our communion; or because miracles are everywhere wrought in it. . . . These things are indeed to be approved, because they are done in the Catholic Church, but it is not thence proved to be the Catholic Church, because such things are done in it. Our Lord Jesus Christ Himself, when He rose from the dead, and offered His body to be touched as well as seen by His disciples, lest there should be any fallacy in it, thought it proper to convince them, rather by the testimony of the Law, the Prophets, and the Psalms, showing how all things were fulfilled which had been foretold; and so He commanded His Church, saying, that repentance and remission of sins should be preached in His Name, among all nations, beginning at Jerusalem. This He testified was written in the Law, the Prophets, and the Psalms; this we hold, as commended from His mouth. These are the documents, these the foundations, these the strong grounds of our cause. We read in the Acts of the Apostles (Acts 17:11), of some believers, that they daily searched the Scriptures if these things were so. What Scriptures? but the canonical books of the Law and the Prophets; to which are added the Gospels, the Apostolical Epistles, the Acts of the Apostles, and the Revelation of St. John, Search, then, all these, and bring forth something manifest, by which you may prove the Church to have remained only in Africa, or come out of Africa in order that it might be fulfilled which the Lord said, “And this gospel of the kingdom will be preached in all the world as a witness to all the nations, and then the end will come.” For translation, see Charles Hastings Collette, Saint Augustine: A Sketch of His Life and Writings, A.D. 387-430 (London: W. H. Allen & Co., 1883), pp. 48-49. De Unitate Ecclesiae, Caput XIX, §47-51, PL 43:430.
David King wrote, citing Joseph Ignaz Von Dollinger, the Roman Catholic historian who opposed the Infallibility of the Pope dogma in 1870:
“But of all the works of Augustine that have been translated, there is one work, De Unitate Ecclesiae that has never been fully translated into English; . . .
But in his controversy with the Donatists, Augustine wrote this work to refute their schism from the Church Catholic. Notice how Augustine does not lodge his argument in an appeal to apostolic succession in this particular work, in fact he bids his adversaries not to look in the direction of human testimonies. Over and over, he argues with the Donatists that the church is to be found in and defined by the Scriptures. Obviously, Augustine did not share the skeptical pessimism of our present day opponents with respect to the testimony of Holy Scripture. Of Augustine’s writings and this one in particular, Johann Joseph Ignaz von Döllinger observed:
“St. Augustine has written more on the Church, its unity and authority, than all the other Fathers put together. Yet, from all his numerous works, filling ten folios, only one sentence, in one letter, can be quoted, where he says that the principality of the Apostolic Chair has always been in Rome,—which could, of course, be said then with equal truth of Antioch, Jerusalem and Alexandria. Any reader of his Pastoral Letter to the separated Donatists on the Unity of the Church, must find it inexplicable, on the Jesuit theory, that in these seventy-five chapters there is not a single word on the necessity of communion with Rome as the centre of unity. He urges all sorts of arguments to show that the Donatists are bound to return to the Church, but of the Papal Chair, as one of them, he knows nothing. “
See Janus, The Pope and the Council, trans. from the German, 2nd ed. (London: Rivingtons, 1869), pp. 88-89.
The Islamic Invasions and conquests - wiping out Christianity in North Africa:Age of the Caliphs
Muhammad, 622–632/A.H. 1-11 Expansion under
Rashidun Caliphate, 632–661/A.H. 11-40 Expansion during the
Umayyad Caliphate, 661–750/A.H. 40-129 Expansion during the
A.H. = After the Hegira (Muhammad's flight to Medina from Mecca in 622 AD)
Sad Reality of Church History in North Africa: Donatist Controversy, Vandals Invade, Muslims Invade and Conquer
The sad reality of church history is that the Donatist controversy sapped the life out of the church in N. Africa (In summary, it seems that the violence and lack of flexibility of the Donatists, coupled with the Catholic church at that time labeling them not only schismatics, but eventually heretics outside of the church, Augustine's change from using debate and persuasion to sanctioning the state to use force and violence to 'compel them to come in', and the state using force, based on Augustine's statement, the false doctrine of the Vandals and their violence also; all contributed to the life of the church being gone by the time the Muslims came.) The barbarian invasions, especially the Vandals had a lasting impact upon the next generations. The Vandals were Arian in their theology – they rejected the doctrine of the doctrine of the Deity of Christ, so “a generation arose that did not know the Lord” (see book of Judges 2:10) Between 430 – 632 AD, most of N. Africa became Arians. As a result, when the Arab Muslims invaded after 632 – 732 AD, the peoples of N. Africa, a mixture of the Berbers, Punic, and Latinized Berbers on the coasts with the Vandals and other Germanic invaders, became Muslims, because they had already given up the gospel and the doctrines of the Deity of Christ and the Trinity. Only the Coptic Church in Egypt survived the Arab Muslim invasions in N. Africa. The Coptic Church was Monophysite (or as they like to call themselves, Miaphysite, “that Christ’s divine nature absorbed His human nature”, so that He had only one Divine nature.) Their holding on the doctrine of the Deity of Christ and the Trinity seems to have given them strength to survive under Islamic domination and persecution.
Failure to Contextualize the Gospel for the frontier fields
Today in North African countries such as Morocco, Tunisia, Algeria, and Libya, Muslims make up 96 to 99% of these countries populations. Turkey is 99% Muslim. What happened to Christianity that was once there? The Church in North Africa was once a thriving church, with famous church leaders such as Tertullian in the second century, Cyprian in the 3rd Century, and Augustine of Hippo, the great theologian in the fourth Century. Kane asks the question, “How shall we account for the demise of such a church?”  After mentioning some of the social and political factors that contributed to the fall of the North African church, he writes, “The real reason for the disappearance of the church in North Africa must be sought somewhere else. Actually, the church was not so strong as it appeared. Numerically it was large, but spiritually it was weak. To begin with, it had never become truly indigenous. It was too closely identified with Latin culture and Roman power. The congregations were composed mostly of Latin-speaking people in and around Carthage. Few of the Punic people ever embraced the Christian faith, and the Berbers were left untouched. Because of this the church never took root in the native soil. “
Indeed, historian David F. Wright writes in the Eerdman’s Handbook to the History of Christianity, that Augustine “. . . was born to African parents of Romanized Berber origins in Tagaste in Numidia (modern Algeria) in 354 AD.”  Augustine himself was not Berber in his culture or thinking, but only ethnically tied to his people through his parents. (his father was pagan, but his mother Monica was a Christian, and she has become a very famous one because of her prayers for Augustine.) Augustine's father would be like the second generation son of a Japanese or Arab immigrant born in the U. S. , who has never been to the country of his parents and does not speak the language. This points out one of the most tragic trends in mission history, especially in the history of missions to Muslims: that converts are too often extracted from their own people and eventually take on a new foreign culture, totally separated from their own people and culture, even though many times they are near-neighbors geographically. This is called “extraction Evangelism” by many missiologists, but sometimes it is unavoidable as some believers have eventually fled persecution in Muslim lands.
So, the first reason that Kane gave was a failure to contextualize [by "contextualize" we mean the good and proper kind of contextualization of translation of the gospel into another language and culture and communication of it accurately, not the modern or post-modern extremes of it.] the gospel into the culture of the North Africans. “A second reason of the demise of the church in N. Africa was the failure to give the Scriptures to the people in their own language. They were available in Latin, but no translations were ever made into the language of the Punic people or the Berbers.” The third reason was emphasizing the truth without the love and power to go with it: “Moreover, theological controversies had sapped the energies of the church. Before the time of Augustine, the church had been racked by the Donatist controversy. Theologians, instead of closing their ranks and presenting a united front to the common enemy, were pre-occupied with fratricidal warfare. They were more interested in defending the purity of the gospel than in demonstrating its power.” Of course, the church must do both, defend the purity of the gospel and demonstrate its power by preaching the gospel accurately, defending the truth and being willing to suffer for it; and loving our enemies and living holy lives.
It seems the church had long since "left its first love" (see Revelation 2:4-5), as it had in Asia Minor, in Ephesus especially, and Jesus warned the churches about this issue. There was false doctrine and unholy living in some of the other churches in Revelation 2-3 also. Eventually, the newly converted to Islam, the Seljuk Turks in the 900s to 1071 AD conquered the eastern areas of Anatolia known as Turkey today. Then came the Crusades (1095-1299 AD); then the Ottoman Turks conquered the rest of the Byzantine Empire. Constantinople fell in 1453 AD and was renamed Istanbul.
As we have pointed out before, Muhammad, the founder of Islam, never heard the gospel or the full truth of the Bible in his own language. The Bible was not translated into Arabic until around 900 AD. Muhammad heard that Jesus was the Messiah ( Al Masih); that He was born of the virgin Mary, and did miracles, was sinless, and had "the Gospel" (the Injeel), but he thought the Trinity was God, the Son Jesus, and the mother, Mary. (Surah 5:116; 5:72-75; 6:101). He said that Jesus the Messiah was not crucified. (Qur'an, Surah 4:157) He said Jesus was not the Son of God and was only a prophet. ( Surah 4:171) This is proof that that the Qur'an is not inspired by God, as it denies clear historical facts, doesn't get the doctrine of the Trinity right, and denies things that Christians had been teaching for around 600 years. False doctrine had corrupted the churches; they exalted Mary too much. The combination of both sound doctrine and evangelism and missions is so important.
Muslims use Surah 2:78-79 to accuse Christians and Jews of making up Scriptures. The context there in the Qur'an is the Jews at the time of Moses. It says that there are some illiterate folk who only know the Scriptures through hearsay; and then it pronounces a "woe" on them that write something and say, "this is from Allah". This is honestly what Muhammad seems to have done. They admit he was illiterate and the Bible was not in Arabic yet. Which one gives the greater historical evidence of just "making up Scriptures"? Who is the one who just "heard" about some stuff without actually knowing what the Scriptures taught?
 J. Herbert Kane, A Global View of Christian Missions, Baker Books, 1971, pp. 52.
 Ibid, p. 52.
 David F. Wright, “Augustine of Hippo”, in Eerdman’s Handbook to the History of Christianity, edited by Tim Dowley, Eerdman’s, 1977, p. 198.
 Kane, p. 52.
 Ibid, Kane, p. 52.
For an interesting read of the History of the Donatists, and perspective that they were falsely accused and unjustly persecuted, first by Constantine, then Augustine himself. It seems Augustine started with argument, debate, and persuasion, as we see in the quotes above in this post, but later justified the use of force.
Augustine's Letter 173, written in 416 AD, where he [wrongly] uses the passage in Luke 14:23, "compel them to come in" as justification for state and police force against the Donatists. This famous mis-usage of Scripture by Augustine was subsequently used a lot by many in Church history to justify the use of force against heretics, schismatics, inquisitions, crusades, etc.
Years ago, a pastor said to me, when I was first studying the Early Church Councils, schisms, excommunications, etc. and then the application of harshness of some of them in church history, namely against the Donatists in N. Africa, the Monosphysites in Egypt, Syria, and Armenia, and the Nestorians in Persia (Mesopotamia, today's Iraq): "The balance of mercy and love was needed with the battle for truth in "contend earnestly for the faith" (Jude 3)". See I Peter 3:15, Jude 20-23, and Ephesians 4:15.