See E. J. Martin, A History of the Iconoclastic Controversy (1930, repr. 1978); J. Pelikan, Imago Dei (1990).
People who engage in or support iconoclasm are called iconoclasts, a term that has come to be applied figuratively to any person who breaks or disdains established dogmata or conventions. Conversely, people who revere or venerate religious images are called 'iconolaters'. In a Byzantine context they are known as 'iconodules', or 'iconophiles'.
Iconoclasm may be carried out by people of a different religion, but is often the result of sectarian disputes between factions of the same religion. The two Byzantine outbreaks during the 8th and 9th centuries were unusual in that the use of images was the main issue in the dispute, rather than a by-product of wider concerns. In Christianity, iconoclasm has generally been motivated by a literal interpretation of the Ten Commandments, which forbid the making and worshipping of "graven images".
As with other doctrinal issues in the Byzantine period, the controversy over iconoclasm was by no means restricted to the clergy, or to arguments from theology. The continuing cultural confrontation with, and military threat from, Islam probably had a bearing on the attitudes of both sides. Iconoclasm seems to have been supported by many from the East of the Empire, and refugees from the provinces taken over by the Muslims. It has been suggested that their strength in the army at the start of the period, and the growing influence of Balkan forces in the army (generally considered to lack strong iconoclast feelings) over the period may have been important factors in both beginning and ending imperial support for iconoclasm.
The use of images had probably been increasing in the years leading up to the outbreak of iconoclasm. One notable change came in 695, when Justinian II put a full-face image of Christ on the obverse of his gold coins. The effect on iconoclast opinion is unknown, but the change certainly caused Caliph Abd al-Malik to break permanently with his previous adoption of Byzantine coin types to start a purely Islamic coinage with lettering only. A letter by the patriarch Germanus written before 726 to two Iconoclast bishops says that "now whole towns and multitudes of people are in considerable agitation over this matter" but we have very little evidence as to the growth of the debate.
"Supported by the Holy Scriptures and the Fathers, we declare unanimously, in the name of the Holy Trinity, that there shall be rejected and removed and cursed one of the Christian Church every likeness which is made out of any material and colour whatever by the evil art of painters.... If anyone ventures to represent the divine image (χαρακτήρ, charaktēr) of the Word after the Incarnation with material colours, let him be anathema! .... If anyone shall endeavour to represent the forms of the Saints in lifeless pictures with material colours which are of no value (for this notion is vain and introduced by the devil), and does not rather represent their virtues as living images in himself, let him be anathema!"
"Satan misled men, so that they worshipped the creature instead of the Creator. The Law of Moses and the Prophets cooperated to remove this ruin...But the previously mentioned demiurge of evil...gradually brought back idolatry under the appearance of Christianity."It was also seen as a departure from ancient church tradition, of which there was a written record opposing religious images.
The chief theological opponents of iconoclasm were the monks Mansur (John of Damascus), who, living in Muslim territory as advisor to the Caliph of Damascus, was far enough away from the Byzantine emperor to evade retribution, and Theodore the Studite, abbot of the Stoudios monastery in Constantinople.
John declared that he did not venerate matter, "but rather the creator of matter." However he also declared, "But I also venerate the matter through which salvation came to me, as if filled with divine energy and grace." He includes in this latter category the ink in which the gospels were written as well as the paint of images, the wood of the Cross, and the body and blood of Jesus.
The iconodule response to iconoclasm included:
It is essential to mention that within Muslim history, the act of removing idols from the Holy Ka'ba is considered by all believers to be of great symbolic and historical importance. In general, Muslim societies have avoided the depiction of living beings (animals and humans) within such sacred spaces as mosques and madrasahs. This opposition to figural representation is not based on the Qur'an, but rather on various traditions contained within the Hadith. The prohibition of figuration has not always extended to the secular sphere, and a robust tradition of figural representation exists within Muslim art. However, western authors have tended to perceive "a long, culturally determined, and unchanging tradition of violent iconoclastic acts" within Islamic society. For example, the destruction of the monumental statues of the Buddha at Bamyan by the Taliban in 2001 was widely perceived in the Western media as a result of the Muslim prohibition against figural decoration. Such an account overlooks "the coexistence between the Buddhas and the Muslim population that marveled at them for over a millennium" before their destruction. The Buddhas had however twice in the past been attacked by the less efficient artillery of Nadir Shah and Aurengzeb. According to Flood, analysis of the Taliban's own declarations regarding the Buddhas suggest that their destruction was motivated more by political than by theological concerns. However, many different explanations of the motives for the destruction have been given by Taliban figures.
The first act of Muslim iconoclasm was committed by Muslims in 630, when the various statues of Arabian deities housed in the Kaaba in Mecca were destroyed, although there is a tradition that Muhammad spared a fresco of Mary and Jesus. This act was intended to bring an end to the idolatry which, in the Muslim view, characterized Jahiliyya.
The destruction of the icons of Mecca did not, however, determine the treatment of other religious communities living under Muslim rule after the expansion of the caliphate. Most Christians under Muslim rule, for example, continued to produce icons and to decorate their churches as they wished. There was one major exception to this pattern of tolerance in early Islamic history: the "Edict of Yazīd," issued by the Umayyad caliph Yazid II in 722-723. This edict ordered the destruction of crosses and Christian images within the territory of the caliphate. It seems to have been followed to a certain degree, particularly in present-day Jordan, where archaeological evidence exists for the removal of images from the mosaic floors of some, although not all, of the churches that stood at this time. However, Yazīd's iconoclastic policies were not maintained by his successors, and the production of icons by the Christian communities of the Levant continued without significant interruption from the sixth century to the ninth.
Despite a religious prohibition on destroying or converting houses of worship, certain conquering Muslim armies have used local temples or houses of worship as mosques. An example is Hagia Sophia in Istanbul (formerly Constantinople), which was converted into a mosque in 1453. Most icons were desecrated whilst the rest were covered with plaster. In the 1920s, Hagia Sophia was converted to a museum, and the restoration of the mosaics was undertaken by the American Byzantine Institute beginning in 1932. More dramatic cases of iconoclasm by Muslims are found in parts of India where Hindu and Buddhist temples were razed and mosques raised on their place (for example, the Qutub Complex).
Certain Muslim denominations continue to pursue iconoclastic agendas, and there has been much controversy within Islam over the recent, and apparently on-going, destruction by the Wahhabist authorities of Mecca of historic buildings (not images as such) which they feared were or would become the subject of "idolatry".
Some of the Protestant reformers, in particular Andreas Karlstadt, Huldrych Zwingli and John Calvin encouraged the removal of religious images by invoking the Decalogue's prohibition of idolatry and the manufacture of graven images of God. As a result, statues and images were damaged in spontaneous individual attacks as well as unauthorised iconoclastic riots. However, in most cases images were removed in an orderly manner by civil authorities in the newly reformed cities and territories of Europe.
Significant iconoclastic riots took place in Zürich (in 1523), Copenhagen (1530), Münster (1534), Geneva (1535), Augsburg (1537), and Scotland (1559). The Seventeen Provinces (now the Netherlands and Belgium and parts of Northern France) were hit by a large wave of Protestant iconoclasm in the summer of 1566. This is called the "Beeldenstorm" and included such acts as the destruction of the statuary of the Monastery of Saint Lawrence in Steenvoorde after a "Hagenpreek", or field sermon, by Sebastiaan Matte; and the sacking of the Monastery of Saint Anthony after a sermon by Jacob de Buysere. The "Beeldenstorm" marked the start of the revolution against the Spanish forces and the Catholic church. See Flanders for more on its history.
During the English Civil War, Bishop Joseph Hall of Norwich described the events of 1643 when troops and citizens, encouraged by a Parliamentary ordinance against superstition and idolatry, behaved thus:
Lord what work was here! What clattering of glasses! What beating down of walls! What tearing up of monuments! What pulling down of seats! What wresting out of irons and brass from the windows! What defacing of arms! What demolishing of curious stonework! What tooting and piping upon organ pipes! And what a hideous triumph in the market-place before all the country, when all the mangled organ pipes, vestments, both copes and surplices, together with the leaden cross which had newly been sawn down from the Green-yard pulpit and the service-books and singing books that could be carried to the fire in the public market-place were heaped together'.
The keen puritan William Dowsing was commissioned and salaried by the government to tour the towns and villages of East Anglia destroying images in churches. His detailed record of his trail of destruction through Suffolk and Cambridgeshire survives:
We brake [sic] down about a hundred superstitious pictures; and seven fryers [sic] hugging a nun; and the picture of God, and Christ; and divers others very superstitious. And 200 had been broke down afore I came. We took away 2 popish inscriptions with Ora pro nobis and we beat down a great stoneing cross on the top of the church. (Haverhill, Suffolk, January 6, 1644)
Protestant Christianity, however, was not uniformly hostile to the use of religious images. Martin Luther argued that Christians should be free to use religious images as long as they did not worship them in the place of God. Zwingli and others for the sake of saving the Word rejected all plastic art; Luther, with an equal concern for the Word, but far more conservative, would have all the arts to be the servants of the Gospel.
“I am not of the opinion” said Luther, “that through the Gospel all the arts should be banished and driven away, as some zealots want to make us believe; but I wish to see them all, especially music, in the service of Him Who gave and created them.” Again he says: “I have myself heard those who oppose pictures, read from my German Bible. … But this contains many pictures of God, of the angels, of men, and of animals, especially in the Revelation of St. John, in the books of Moses, and in the book of Joshua. We therefore kindly beg these fanatics to permit us also to paint these pictures on the wall that they may be remembered and better understood, inasmuch as they can harm as little on the walls as in books. Would to God that I could persuade those who can afford it to paint the whole Bible on their houses, inside and outside, so that all might see; this would indeed be a Christian work. For I am convinced that it is God’s will that we should hear and learn what He has done, especially what Christ suffered. But when I hear these things and meditate upon them, I find it impossible not to picture them in my heart. Whether I want to or not, when I hear, of Christ, a human form hanging upon a cross rises up in my heart: just as I see my natural face reflected when I look into water. Now if it is not sinful for me to have Christ’s picture in my heart, why should it be sinful to have it before my eyes?”