We have seen that, as early as Augustine’s treatise on The City of God, this complaint had been addressed. What was the distinction between the veneration of the saints and the worship of God? The issue was clarified in the Christian East during the eighth and ninth centuries during the controversy known as iconoclasm. A strong reaction against the use of painted images of Christ, Mary, the angels, and the saints erupted in the world of Byzantium. Icons were destroyed in many places and users of icons were punished and even executed. The reasons for this iconoclastic outbreak have been debated, but many influences may be alleged: iconoclasm was a final reaction against paganism; there was the absolute prohibition of images clearly stated in the Old Testament; and, finally, there may have been influences coming from the rise of Islam and its total rejection of any kind of pictorial art.
Supporters of the use of icons in piety (the so-called “iconodules” or “image venerators”) were forced to make some careful distinctions in order to resist the logic of the iconoclasts. At the most elementary level, they made a distinction between an idol (Greek: eidolon) and an image (Greek: eikon). The former was worshiped in the pagan world, while the latter was only venerated as a vehicle to go beyond the image to the reality behind it. The defenders of icons did not at all defend the worship of idols.
Second, and more importantly, the defenders of the use of icons distinguished the veneration of icons as sacred or holy objects from the worship of the person(s) depicted. They then further distinguished the absolute worship of God from the veneration due the saints. The greatest of the defenders of the use of icons was Saint John of Damascus (c.655–750) who wrote three treatises between 726 and 730 defending the use of icons. From his writings we have a set of crucial distinctions which may be summarized as follows: we honor (Greek: time) sacred images, we venerate (Greek: proskynesis) those who are depicted in the images, but we worship (Greek: latreia) God alone.
The iconoclastic controversy was so heated and divisive in the Byzantine world that in order to settle the controversy an ecumenical council was convened in 787 at Nicaea. This Second Council of Nicaea was the last one held by the undivided churches of the East and West. The conciliar documents affirmed the legitimacy of painted representations because they reminded people of the truths of the Bible (i.e. they had a pedagogical value) and inspired people to greater piety, while reminding people that such persons as those depicted were not mythical or fictive but real personages who lived and live. The decree then adds: “Indeed, the honor paid to an image traverses it, reaching the model and the one who venerates the image, venerates the person represented in that image.”
Even though the Council did not definitively settle the iconoclastic controversy, it did mark the beginning of the end for the image-breakers’ movement. The decision in favor of the legitimacy of icons was crucial for the Byzantine Church since the place of icons in its practice is one of its signal characteristics. It is a mark of the importance of that event that to this day the Byzantine calendar celebrates annually the feast called “The Triumph of Orthodoxy” to commemorate the decision made in Nicaea in 787.