Question: "How was the gospel preserved during the Middle Ages?"
Answer: Throughout the centuries, God has preserved His Word and has raised up men and women for the task. Even during the Middle Ages, sometimes called the “Dark Ages” because of a perceived lack of knowledge during that time, the truth of the gospel was available. It is true that the Roman Catholic Church and the Holy Roman Empire were at the height of their power and a common-language Bible was being suppressed; however, even then, God’s people were active. God’s hand is never “shortened that it cannot save” (Isaiah 59:1). His truth was marching on.
The Church had already survived much persecution under various Roman Emperors, including the Great Persecution under Diocletian between AD 303 and 313. Constantine put an end to the persecution after he became Emperor, and Christianity was eventually made the state religion of Rome.
As Rome began consolidating its power over the Church, there were dissenters who refused to acknowledge the bishop of Rome as their head. One such dissenter was the North African Bishop Donatus, who stood against Rome’s understanding of the sacraments and infant baptism. The Donatists were condemned by the churches in Europe, but they continued to be a light for the gospel of grace in the days of Constantine. Other men who fought for truth against early heresies were Bishops Alexander and Athanasius. Later, the gospel began to be preached as far away as Ireland (from AD 432) by Patrick. The Bible was also translated into Latin, and the gospel spread throughout Europe.
The Middle Ages, which lasted from about the 5th to the 15th century, was dominated in Europe by the Holy Roman Empire. This was the time of the Crusades, the Great Schism, the Inquisition, and the iron rule of the Roman Catholic Church. Throughout this difficult time, God still had witnesses to the truth.
When infant baptism was introduced by the Church of Rome, various churches dissented and denounced the practice. In the 11th and 12th centuries, the Petrobrusians rejected infant baptism. They became known as Anabaptists. They re-baptised believers who had been baptized as infants, maintaining that baptism is only valid if it was a conscious act of faith by the believer. The Anabaptists survived intense persecution and still exist today. From the Anabaptists the English Baptists came to prominence in the mid-1600s.
A group called the Waldensians was started in 1170 in Lyons, France, by a wealthy man named Valdes (Peter Waldo). He valued poverty as the basis for Christian life and the necessity for all Christians to preach the gospel. The Waldensians continued to expand but became increasingly estranged from the Roman Church over their doctrine, and in 1184 a papal bull was issued against them. Other reform groups existing before the Protestant Reformation were the Novatians, the Albigenses, the Petrobrussians, the Paulicians, the Cathari, the Paterines, the Lollards, and more.
Long before Martin Luther posted his 95 Theses on the door of the Castle Church in Wittenberg in 1517, there were men who had stood up for reform and the true gospel. Among them were John Wycliffe, an English theologian and Oxford professor who was condemned as a heretic in 1415 for teaching that the common people should have access to the Bible; Jan Hus, a priest from Bohemia who was burned at the stake in 1415 for his opposition to the Church of Rome; and Girolamo Savonarola, an Italian friar who was hanged and burned in 1498.
During the 16th century, other godly men stood in opposition to the Church of Rome—Jakob Hutter (founder of the Hutterites), John Knox of Scotland, William Tyndale (martyred for translating the New Testament into English), John Calvin of France, Ulrich Zwingli of Switzerland, and the English reformers Cranmer, Latimer, and Ridley (all burned at the stake).
God has had a faithful remnant in every age. In the time before the Flood, Noah found grace in God’s eyes. During the time of the judges, there were still faithful men like Gideon, Barak, and Boaz and faithful women like Hannah, Deborah, and Ruth. During the reign of Ahab and Jezebel, there were seven thousand people who stood firm against Baal worship (1 Kings 19:18). Just as God raised up faithful men and women in biblical times in the outworking of His divine plan, so He raised up faithful men and women during the Middle Ages. They were all sinners, flawed and imperfect characters, but God took what was weak and imperfect and turned them to His glory. Those faithful Christians were used by God “to contend earnestly for the faith that was once for all delivered to the saints” (Jude 1:3). In spite of all the conflicts, schisms, and bloodshed that accompanied the growth of the Church up to and beyond the Reformation, the gospel message has been preserved.