Trinitarian apologist’s who study church history like Dr. Steve Morrison and Dr. Edward Dalcour insist that Trinitarians were always among the majority of Christians in the second and third centuries, but Tertullian and Origen stated that the majority of believers at that time favoured the Sabellian view of the oneness of God. (Tertullian, Against Praxeas, III, c.213 / Origen’s Commentary of the Gospel of John, book 1, chapter 23)
Roman Catholic Cardinal and historian JOHN HENRY NEWMAN wrote in his book, “The Arians of the Fourth Century” – Under Sabellianism (LONGMANS, GREEN, AND CO. / 39 PATERNOSTER ROW, LONDON, NEW YORK, BOMBAY, AND CALCUTTA - 1908, SABELLIANISM, Pg. 118),
“The ‘speculations’ of ‘Praxeus’ (A prominent Modalistic Leader in the late second and early third century) remained alive in that part of the world, though latent [Note 3 - Tertull. in Prax.], till they burst into a flame about the middle of the third century, at the eventful era when the rudiments of Arianism were laid by the sophistical school at Antioch.” (Trinitarian Church Historian John Henry Newman’s Book, Arians of the Fourth Century, Chapter 1, Section 5, under “Sabellianism”)
John Henry Newman stated that “speculations” about the teachings of Praxeus “remained alive in that part of the world” before bursting out into a flame in the middle of the third century in reaction to the form of Semi-Arian theology that predated the theology of Arius. If the theology of Praxeus had “remained alive” within the hearts and minds of the Christian majority, then these Christians could not have been Trinitarian in their thinking. The context of chapter 1, Section 5B (Page 119) proves that the Sabellian theology “became so popular among the clergy already prepared for it … that in a short time (to use the words of Athanasius) ‘The Son of God was SCARCELY PREACHED IN THE CHURCHES.’” (Trinitarian Church Historian John Henry Newman’s Book, Arians of the Fourth Century, Chapter 1, Section 5, under “Sabellianism”)
If the Athanasian view of the Son of God was “scarcely preached in the churches” before the time of Athanasius, then that would mean that the Athanasian Trinitarian view was once scarce, and that the Sabellian view was “popular among a clergy already prepared for it.” Thus, even many Trinitarian historians admit that Oneness Modalism was the most popular ancient Christian theology before the time of Athanasius even though some Trinitarian apologists like Dr. Dalcour and Dr. Morrison deny the clear historical evidence.
Church historian B. B. Edwards wrote, “Epiphanius (Haeres 62) about 375 AD notes that the adherents of Sabellius were still to be found in great numbers, both in Mesopotamia and at Rome. The first general council at Constantinople in 381 in canon VII and the third general council at Constantinople in 680 in canon XCV declared the baptism of Sabellius to be invalid, which indicates that Sabellianism was still extant.” (“THE BIBLICAL REPOSITORY AND QUARTERLY OBSERVER. By B. B. EDWARDS” Under Views of Sabellius, The Biblical Repository and Classical Review, American Biblical Repository)
Since Oneness (Sabellian) adherents “were still to be found in great numbers” in “about 375 AD,” it is hard to believe that Oneness believers were not also “still to be found in great numbers” during the Council of Nicaea, just fifty years earlier.
Church historian B. B. Edwards wrote, “That the opinions of Sabellius were urged with zeal and ability by him, seems altogether probable from the fact, that many bishops in the neighbouring countries, and in Egypt, received them. Moreover the burning zeal which Dionysius bishop of Alexandria (Cardinal John Newman wrote in his book “Arianism in the fourth Century.” “… later writers, and even Basil himself, do not scruple to complain of Dionysius as having sown the first seeds of Arianism) manifests against them, shows that he felt the danger from them to be great. His excessive sensitiveness also betrays the conviction in his mind, that they would soon become predominant. It is probable, that his strenuous efforts to suppress Sabellianism, joined with the successive ones of Athanasius, Basil, and others, may have checked very much the rapid progress which it was making. Epiphanius however, (Haeres. 62) about A. D. 375, testifies that the adherents of Sabellius were still to be found in great numbers, both in Mesopotamia and at Rome. Facts like these account for the uncommon zeal which Dionysius, Athanasius, and Basil, as well as Hilary and others, show against what they supposed to be Sabellianism. They show us, also, that many in the churches were stumbled at the hypostatic theory of the Alexandrine School (Origen’s school), and eagerly embraced an opportunity to throw it off ...” (“THE BIBLICAL REPOSITORY AND QUARTERLY OBSERVER. By B. B. EDWARDS” Under Views of Sabellius, The Biblical Repository and Classical Review, American Biblical Repository)