There are glimpses of Protestant teachings from earliest Christian times to the Dark Ages. The Epistle of Barnabas explains a typical significance of the Sabbath: “The meaning of it is this: that in six thousand years the Lord God will bring all things to an end. For with him one day is a thousand years … And he rested the seventh day: he meaneth this; that when his Son shall come, and abolish the season of the Wicked One, and judge the ungodly; and shall change the sun and the moon, and the stars; then he shall gloriously rest in that seventh day. … the Sabbaths, says he, which ye now keep are not acceptable unto me, but those which I have made; when resting from all things I shall begin the eighth day, that is, the beginning of the other world.”1
Willingness to suffer martyrdom for the cause of Christ is illustrated in Ignatius’ Epistle to the Romans (ca. A.D. 110) 2:2-4, “Suffer me to be food to the wild beasts; by whom I shall attain unto God. For I am the wheat of God; and I shall be ground by the teeth of the wild beasts, that I may be found the pure bread of Christ. Rather encourage the beasts, that they may become my sepulcher; and may leave nothing of my body; that being dead I may not be troublesome to any.”
Similarly, the contemporary Polycarp writes,2 “I exhort all of you that ye obey the word of righteousness, and exercise all patience; which ye have seen set forth before our eyes, not only in the blessed Ignatius, and Zozimus, and Rufus; but in others among yourselves; and in Paul himself, and the rest of the apostles.”
We hear of Arius first in A.D. 313 pleading for restoration of primitive purity in an Alexandrian church gone worldly. The leader of the worldly faction, Athanasius, could hardly accuse Arius of being too honorable; so after five years he accused Arius of heresy for not calling God a Trinity.3 Ultimately the Athanasians poisoned Arius to death and called it the righteous judgment of God.
About A.D. 538, Jacobus Baradaeus (literally, James of rags, as he declined to spend money on clothing), of Syria, defended the monophysite concept of Jesus at his first advent having just one nature, the human. He ranged from Egypt to Babylon and ordained 80,000 bishops. (The modern Syrian Orthodox Church descended from him, and remains Monophysite.)
The Paulicians in Asia were outside the Catholic Church, and began evangelizing in Europe. Likely from them came the moderate Cathars (lit. Puritans, though the Catholic hierarchy called them “Ketzer,” heretics). Already in A.D. 1140, in Monteforte, they said Jesus did not have a soul, but by identity he was a soul. They looked forward to the “Rejuvenation Day.”
Other notable pre-Reformation Christians include Peter Waldo and the Waldenses in the Alps; John Wycliffe, who before William Tyndale’s time translated the Bible into English (though it would be incomprehensible a century later), had followers who were called Lollards; Jan Hus in Poland/Czech Republic; and Johann Wessel-Gansfort in the Netherlands, who said, “It is not by works, but in works, that faith lives.” All faced opposition, most were hunted, and some were burned at the stake.
1. Epistle of Barnabas 13:1-10. (Likely the Barnabas who was with Paul.)
2. Epistle of Polycarp (bishop of Smyrna) to the Philippians 3:5-9.
3. Curiously, the word Trinitatis was invented by Tertullian ca. A.D. 200, but he was outside the main body of professing Christians. Irenaeus did not share the concept, but he was declared a Catholic saint, not Tertullian.