During the first phase of the Iconoclastic Controversy (717–787), John of Damascus emerged as the chief spokesman of the iconodules. His apologetic for icons, developed in his Treatises Against Those Who Attack the Holy Images (around 730) provided the rationale for the dogmatic decree legitimizing icons, which was adopted at the Seventh Ecumenical Council (Nicea II, 787). Exegetical, hermeneutical, and christological arguments played the dominant roles in his defense of the legitimacy of icons. An additional element in the Damascene's apologetic was an innovative theory of human cognition which placed a high value on created materiality, and thus extended the traditional Eastern Christian appreciation of the material world.

Early in his career, when he still trusted in the power of councils to effect reform, Martin Luther wrote: [The Romanists] are not empowered to prohibit a council or, according to their pleasure, to determine its decisions in advance, to bind it and to rob it of freedom. But if they do so, I hope to have shown that of a truth they belong to the community of Antichrist and the devil.” Some seventy years before Luther's appeal to the German nobility, however, the Spanish theologian and noted conciliarist, Juan de Segovia, who championed the authority of councils throughout his career, had already drawn a more startling connection between the chief “Romanist” opponent of councils and the spiritual adversaries of Christendom. For, in several works written in the 1450s, Segovia identified Pope Eugenius IV with Lucifer.

The historical development of explicit forms of Christian mysticism can be sketched according to a model of gradually accumulating and interactive layers of tradition. The monastic ideal of flight from the world in order to lead a specialized life of penance and prayer, either as a hermit or within a community, formed the institutional context for most forms of Christian mysticism down to the end of the twelfth century. This monastic layer of mysticism was primarily biblical and liturgical in the sense that it sought God in and through personal appropriation of the mystical understanding of the Bible as cultivated within the liturgical life of the monastic community. Most monastic mystics were also “objective” in the sense that they rarely talked about their own experiences of God, but rather sought to express their understanding of mystical transformation through biblical exegesis and theoretical expositions of a mystagogical character (that is, expositions designed to lead readers into the mystery of the consciousness of God's presence)

Within their considerable rhetorical arsenal, perhaps the favorite accusations that sixteenth-century Calvinist Reformers lodged against the medieval church and the pious conduct of its followers were those of “superstition and idolatry.” Prominent leaders such as John Calvin and Theodore Beza, erudite theologians and celebrated preachers, local pastors and village elders alike stood ever ready to apply the designations to a variety of religious convictions and habits that they considered the incorrect belief and inappropriate behavior of the uninformed and vulgar. This Calvinist campaign against the superstitious and idolatrous went well beyond an attack on such unscriptural matters as belief in purgatory, veneration of images and relics, or invocation of the saints. It also manifested a deeply felt animosity toward papal Christianity—a hostility often expressed in dramatic and powerful language. One particularly intense example comes from the southern French town of Marsillargues during the early seventeenth century. When two men, who had converted to Calvinism, reverted to their earlier Catholicism several months later, the local Reformed church condemned them for having returned to their “vomit” and “slime.”

The name “John Calvin” and the movement associated with him, Calvinism, serve as rhetorical negatives in the popular language of American culture. In a society often regarded as the most ahistorical in the Western world—an important American proclaimed that “history is bunk”—the name of Calvin, the sixteenth-century Protestant reformer who worked mostly in Geneva, is common enough coinage to show up in a variety of contexts. One can read newspaper stories on baseball, and Calvin is there. Or one can look at a popular book on the drug Prozac and there read about “pharmacological Calvinism.” A moving analysis of the AIDS crisis in the New York Times mentions Calvin. All of the references carry negative connotations of fatalism, guilt, and so on. The word “Calvin” seems to be shorthand for a range of negative thoughts and feelings in the American cultural consciousness.