The most famous and important of the anti-clerical agitators was John Wycliff who originally began his career as a doctor of divinity at Oxford in the 1360's and speculated on such abstruse questions as the nature of universals. He soon, however, developed strong critiques of the church and eventually assumed in the late 1370's a revolutionary stance towards the church. He rejected all church hierarchy and declared that the Christian consisted of the people who had faith but did not consist of the church hierarchy (this would eventually become the "priesthood of all believers" in Martin Luther). He rejected transubstantiation as a legitimate doctrine (the idea that the bread and wine of the Eucharist actually change into the body and blood of Christ), arguing that there is no Scriptural authority for this. He also argued that the Bible should be translated into vernacular languages, that it does no good to read from the Bible in a language that most Christians can't understand. To this end, he produced the first English Bible.
Wycliff's radical ideas led to a distinct anti-clerical movement in England: Lollardry. Lollard ideas in part impelled the Peasant's Rebellion of 1381 and would surface in the remainder of the century. While Lollardry was effectively stamped out in the early 1400's, it re-emerged with a vengeance when Protestantism was introduced into England in the 1510's. Lollard ideas, however, did diffuse across the continent and many of the theological and social ideas of the Protestant Reformation are traceable back to the hapless Lollards.
The most important thing about Lollardry and the general anti-clericalism of the fourteenth century is that it founded a new culture deliberately resistant to the dominant, homogenizing culture of the church. This new anti-clerical culture led a number of theologians, writers, and poets in England to begin to speculate about the nature of society, government, economics and human institutions and to forge radically new ideas on all these fronts. Any speculation about the legitimacy of political power would have landed the writer in serious trouble; church government, however, was relatively open to criticism and it was here that the critical tradition in European political theory developed, and in no place in Europe did it develop as strongly as it did in medieval England.
The anti-clerical culture was not so much a theological or even a doctrinal culture—it was a moral and political culture in part forged out of the increasing role that all individuals were playing in English government. Anti-clerical culture manifested itself in religious works, such as Piers Plowman written by a desperately poor cleric named William Langland, in mystical literature such as The Book of Margery Kempe, and in an entire corpus of secular literature and practices.