The reader will find all the information he desires with regard to the great iconoclastic controversy in the ordinary church-histories, and the theological side of the matter in the writings of St. John Damascene. It seems, however, that in order to render the meaning of the action of the last of the Ecumenical Councils clear it is necessary to provide an account of the synod which was held to condemn what it so shortly afterward expressly approved. I quote from Hefele in loco, and would only further draw the reader's attention to the fact that the main thing objected to was not (as is commonly supposed) the outward veneration of the sacred icons, but the making and setting up of them, as architectural ornaments; and that it was not only representations of the persons of the Most Holy Trinity, and of the Divine Son in his incarnate form that were denounced, but even pictures of the Blessed Virgin and of the other saints; all this is evident to anyone reading the foregoing abstract of the decree. (Hefele, History of the Councils, Vol. V., p. 308 et seqq.)
The Emperor, after the death of the Patriarch Anastasius (a.d. 753), summoned the bishops of his Empire to a great synod in the palace Hieria, which lay opposite to Constantinople on the Asiatic side of the Bosphorus, between Chrysopolis and Chalcedon, a little to the north of the latter. The vacancy of the patriarchate, facilitated his plans, since the hope of succeeding to this see kept down, in the most ambitious and aspiring of the bishops, any possible thought of opposition. The number of those present amounted to 338 bishops, and the place of president was occupied by Archbishop Theodosius of Ephesus, already known to us as son of a former Emperor-Apsimar, from the beginning an assistant in the iconoclastic movement. Nicephorus names him alone as president of the synod; Theophanes, on the contrary, mentions Bishop Pastillas of Perga as second president, and adds, "The Patriarchates of Rome, Alexandria, Antioch, and Jerusalem were not represented [the last three were then in the hands of the Saracens], the transactions began on February 10th, and lasted until August 8th (in Hieria); on the latter date, however, the synod assembled in St. Mary's Church in Blachernae, the northern suburb of Constantinople, and the Emperor now solemnly nominated Bishop Constantine of Sylaeum, a monk, as patriarch of Constantinople. On August 27th, the heretical decree [of the Synod] was published."
We see from this that the last sessions of this Conciliabulum were held no longer in Hieria, but in the Blachernae of Constantinople. We have no complete Acts of this assembly, but its very verbose oroj (decree), together with a short introduction, is preserved among the acts of the Seventh Ecumenical Council.
This decree was by no means suffered to remain inoperative.
(W. M. Sinclair. Smith and Wace, Dictionary of Chr. Biog., sub voce Constantinus VI.)
The Emperor singled out the more noted monks, and required them to comply with the decrees of the synod. In a.d. 766 he exacted an oath against images from all the inhabitants of the empire. The monks refused with violent obstinacy, and Copronymus appears to have amused himself by treating them with ruthless harshness. The Emperor, indeed, seems to have contemplated the extirpation of monachism. John the Damascene he persuaded his bishops to excommunicate. Monks were forced to appear in the hippodrome at Constantinople hand in hand with harlots, while the populace spat at them. The new patriarch Constantinus, presented by the emperor to the council the last day of its session, was forced to foreswear images, to attend banquets, to eat and drinkfreely against his monastic vows, to wear garlands, to witness the coarse spectacles and hear the coarse language which entertained the Emperor. Monasteries were destroyed, made into barracks, or secularized. Lachanodraco, governor of the Thracian Theme, seems to have exceeded Copronymus in his ribaldry and injustice. He collected a number of monks into a plain, clothed them with white, presented them with wives, and forced them to choose between marriage and loss of eyesight. He sold the property of the monasteries, and sent the price to the Emperor.Copronymus publicly thanked him, and commended his example to other governors.
(Harnack. History of Dogma, Vol. V., p. 325 [Eng. Tr.].)
The clergy obeyed when the decrees were published; but resistance was offered in the ranks of the monks. Many took to flight, some became martyrs. The imperial police stormed the churches, and destroyed those images and pictures that had not been secured. The iconoclastic zeal by no means sprang from enthusiasm for divine service in spirit and in truth. The Emperor now also directly attacked the monks; he meant to extirpate the hated order, and to overthrow the throne of Peter. We see how the idea of an absolute military state rose powerfully in Constantinople; how it strove to establish itself by brute force. The Emperor, according to trustworthy evidence, made the inhabitants of the city swear that they would henceforth worship no image, and give up all intercourse with monks. Cloisters were turned into arsenals and barracks, relics were hurled into the sea, and the monks, as far as possible, secularized. And the politically far-seeing Emperor, at the same time entered into correspondence with France (Synod of Gentilly, a.d. 767), and sought to win Pepin. History seemed to have suffered a violent rupture, a new era was dawning which should supersede the history of the Church.
But the Church was too powerful, and the Emperor was not even master of Oriental Christendom, but only of part of it. The orthodox Patriarchs of the East (under the rule of Islam) declared against the iconoclastic movement, and a Church without monks or pictures, in schism with the other orthodox Churches, was a nonentity. A spiritual reformer was wanting. Thus the great reaction set in after the death of the Emperor (a.d. 775), the ablest ruler Constantinople had seen for a long time. This is not the place to describe how it was inaugurated and cautiously carried out by the skilful policy of the Empress Irene; cautiously, for a generation had already grown up that was accustomed to the cultus without images. An important part was played by the miracles performed by the re-emerging relics and pictures. But the lower classes had always been really favourable to them; only the army and the not inconsiderable number of bishops who were of the school of Constantine had to be carefully handled. Tarasius, the new Patriarch of Constantinople and a supporter of images, succeeded, after overcoming much difficulty, and especially distrust in Rome and the East, after also removing the excited army, in bringing together a General Council of about 350 bishops at Nicaea, a.d. 787, which reversed the decrees of a.d. 754. The proceedings of the seven sittings are of great value, because very important patristic passages have been preserved in them which otherwise would have perished; for at this synod also the discussions turned chiefly on the Fathers. The decision (oroj) restored orthodoxy and finally settled it.
I cannot do better than to cite in conclusion the words of the profoundly learned Archbishop of Dublin, himself a quasi-Iconoclast. (Trench. Lect. Medieval Ch. Hist., p. 93.)
It is only fair to state that the most zealous favourers and promoters of this ill-directed homage always disclaimed with indignation the charge of offering to the images any reverence which did not differ in kind, and not merely in degree, from the worship which they offered to Almighty God, designating it as they did by altogether a different name. We shall very probably feel that in these distinctions which they drew between the one and the other, between the "honour" which they gave to these icons and the "worship" which they withheld from these and gave only to God, there lay no slightest justification of that in which they allowed themselves; but these distinctions acquit them of idolatry, and it is the merest justice to remember this. (Trench. Ut supra, p. 99.)
I can close this Lecture with no better or wiser words than those with which Dean Milman reads to us the lesson of this mournful story: "There was this irremediable weakness in the cause of iconoclasm; it was a mere negative doctrine, a proscription of those sentiments which had full possession of the popular mind, without any strong countervailing excitement. The senses were robbed of their habitual and cherished objects of devotion, but there was no awakening of an inner life of intense and passionate piety. The cold, naked walls from whence the Scriptural histories had been effaced, the despoiled shrines, the mutilated images, could not compel the mind to a more pure and immaterial conception of God and the Saviour. Hatred of images, in the process of the strife, might become, as it did, a fanaticism, it could never become a religion. Iconoclasm might proscribe idolatry; but it had no power of kindling a purer faith."