Despite the efforts of Francis of Assisi and others to call the church to reform, by the 15th century the church had become totally identified with the interests of the state and power, and the very notion of Christendom made the powers of church and state inseparable.

Those who challenged the status quo faced being marginalised or condemned as heretics. The 15th century church could live with a visionary like Julian of Norwich (d. ca 1413), so long as she lived (symbolically) outside the walls of the church, but not with a visionary like Joan of Arc, who was burned at the stake for witchcraft and heresy in 1431.

Among the common people, a popular religion had developed with the veneration of saints (particularly the Virgin Mary), relics, shrines and pilgrimages. But the vast majority of people were still excluded from participating in the central sacramental life of the church - when they were present at Mass, they were there as spectators, excluded by and large from the Communion or Eucharist - and from any role in running church affairs.

No longer was the Bible available in the common language, and many received their religious education only through the street plays, the carvings, paintings and stained glass in churches, or the popular cycles of folk religion.

While the early primitive church could benefit from St Jerome's translation of the Bible into the common Latin of daily commerce, the Vulgate, the church in later centuries was unable to accept the demands for translation.

John Wyclif (ca 1329-1384) initiated a new translation of the Vulgate into English, but was soon deserted by his friends in high places, and his followers, the Lollards, were suppressed. However, the demands to have the Bible translated continued apace in England and on the Continent, and the move to return to the original texts and meanings would become an essential part of the scholarship of the Renaissance.

Unlike Francis and Dominic, later critics, including the Waldensians and Hussites, were less successful in seeking to reform the church from within. In France and Italy, the Waldensians were hunted down.

In Central Europe, John Hus (1374-1415), a priest and teacher at the Charles University in Prague, stressed the authority of scripture and gave greater emphasis to preaching. He criticised with equal vigour the superstitions that had crept into popular, folk religion, the corrupt life of his clerical contemporaries, the authority assumed by cardinals and the papacy, and the withholding of the cup of wine from the people during the Communion.

At the Council of Constance in 1415, Wyclif was condemned for heresy and an order was made for his body be disinterred from holy ground; Hus too was condemned as a heretic, and without an opportunity to defend his ideas was burned at the stake. On the other hand, Thomas a Kempis (ca 1380-1471), was able to remain within the church, and influenced many through his preaching, counselling, and books, particularly The Imitation of Christ, which opened the hearts and minds of many to receive the teachings of the Reformers.

The demands for reform refused to go away, and Wyclif and Hus can be seen as precursors of the Reformation. The simple lifestyle of the Hussites and the Waldensians, who were excommunicated, or Thomas a Kempis and the Brethren of the Common Life, who remained inside the church, provided a stark contrast to the lifestyle of many 15th century Popes.

The papacy had already been exposed to criticism through the political power-games of many Popes in the battles between France and Germany, the lengthy absence from Rome of Popes in Avignon, and the consequent schisms and the emergence of rival colleges of cardinals and claimants to the papacy.

With the deposition of rival Popes in 1409, 1415 and 1417, the Councils of Pisa and Constance established an important principle: a council could deprive a pope of his claims to supremacy.

With Sixtus IV (1471-1484), the papacy reached a new low: he made six of his "nephews" cardinals, was implicated in the assassination of two of the Medicis in 1478, and exploited the sale of offices and indulgences.

Alexander VI (1492-1503), father of the infamous Lucretia Borgia, secured his election through bribery and within a year had divided the spoils of the "New World" between Spain and Portugal. The age of discovery coincided with the Renaissance, which gave the church great artists, including Michelangelo and Titian, and the wisdom and erudition of scholars such as Erasmus and Rabelais.

Desiderius Erasmus of Rotterdam (1467-1536) has been described as "the greatest humanist after Petrarch". It is said that he made the Reformation inevitable, and his monastic contemporaries complained that he laid the egg which Luther hatched.

Erasmus was educated by the Brethren of the Common Life in Holland, and joined the Augustinians in 1487. In Paris, Erasmus was strongly critical of the of the nominalist theology at the Sorbonne; in Rome, he was contemptuous of the climate of corruption.

Instead, he turned to the classics and the humanists, became the "journalist of scholarship", edited Jerome's works, and in 1516 published the first printed edition of the Greek New Testament.

His friend Francois Rabelais (1494-1553), mocked the failings of the theology of the Sorbonne and was open to the ideas of the Reformers. But, while satirising the failings of Rome and the Papacy, he remained a priest throughout his life. And yet the Renaissance and the Reformation are inseparable.

After Erasmus and Rabelais, theology could never be the same again. No longer could there be an unquestioning acceptance of received tradition and teachings. The decay in the church had produced the demands for reform, and the Renaissance provided the intellectual methods for those demanding reform.

A year after Erasmus published his Greek New Testament, the Reformation began on October 31st, 1517, when the Professor of Biblical Studies at Wittenberg University nailed his 95 Theses to the door of the Castle Church. Decay and decline left the church too weak to accept or meet the demands for reform.

The reformers had to be dealt with brutally - as the Dominican prior Savonarola had been burned at the stake in Florence - or marginalised and cut off by excommunication. But the demands for reform were coming from within the church, and those leading the demands were among its most able and loyal clergy: an Augustinian friar in Germany, Martin Luther (14831546); a French parish priest, John Calvin (1509-1564); a French Dominican, Martin Bucer (1491-1551), who tried to mediate between Calvin and Luther; and their English contemporary, Thomas Cranmer (1489-1556), a quiet and reluctant scholar from Cambridge who was summoned to become Archbishop of Canterbury as late as 1532, and who would shape the English language through the Book of Common Prayer and his translation of the Psalms.

When it came, the Reformation ought to have been a breath of fresh air through the whole church. Instead, it threatened to bring down the whole edifice.

Rev Patrick Comerford writes on theology and church history and is an Irish Times journalist. Contact: theology@ireland.com

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