Broadly defined as a representation or image intended to depict a concept or quality of particular importance, icons have loomed large in the religious and cultural histories of numerous societies throughout the centuries. Icons have been rendered in media such as stone, fabric, tile mosaic and metal, and have been produced in both two- and three-dimensional formats. The tradition of Byzantine icons is of distinct significance, because the typically two-dimensional, painted likenesses played a critical role in the worship practices of followers of Eastern Christianity from 330 A.D. onward, and they continue to be prized for their meaningful, artistic portrayals of biblical themes.
The most common type of Byzantine icon consists of a flat, painted representation of entities of Christian religious significance such as Christ, Mary, saints and angels. Many other icons function as descriptive narratives of events including the crucifixion of Christ. Depictions were traditionally fashioned to emphasize the holy aura of their subjects, not their corporeality. No single size of Byzantine icon can be said to dominate the category, because these images tend to range from tiny, portable representations to massive panels created to adorn the inside spaces of sacred buildings. Three-paneled triptychs were commonly produced, as were larger panels meant to be hoisted on poles for display during combat.
Each Byzantine icon served a key function for worshipers in Eastern Christianity. According to Byzantine tradition, it was possible to communicate with the entity portrayed on the icon's surface simply by gazing upon it. The belief was that prayers could be channeled specifically to the represented figure, and divine assistance was likely to follow. The Byzantine period saw particular interest in a class of icons referred to as being acheiropoieta, meaning they were thought to be created by virtue of a sacred miracle, rather than by the hands of mortals.
Dating back to Christianity's earliest days, debate regarding the use of images and sacred depictions was prevalent. Biblical warnings against the worshiping of graven images called into the question the appropriateness of icons and the significant role they played in Byzantium. The eighth century saw the emergence of an intense disagreement among religious authorities and the state that resulted in blanket prohibition of the use and creation of icons. Widespread destruction of icons ensued and, therefore, no examples of these images created prior the 11th century remain. After the Iconoclastic Period ended, the Byzantine icon re-emerged as a centerpiece of religious belief and expression throughout the geographical reach of Eastern Christianity.