Some folks seem to find relying on councils a comfort. For these folks, there are some inconvenient facts that they must face. This post is the nineteenth in the multi-part series.
Seventh Ecumenical Council (783) - Destroyed Patristic Writings Opposed to Icons
In mocking words, the council commanded that all writings opposed to icons be turned over to the Patriarch of Constantinople, whose job it was to prevent these writings from being read. This command was to be enforced by deposing clergy from office and excommunicating laymen and monks:
All boyish whimwhams and mad bacchanalia, the false writings that have been brought forth against the venerable icons, must be turned in to the Bishopric of Constantinople to be put away together with the rest of heretical books. If, on the other hand, anyone should be found hiding these, if he be a Bishop, a Presbyter, or a Deacon, let him be deposed from office; but if he be a layman or a monk, let him be excommunicated.
You will notice that, in theory, there was a sort of "heretical library" to be possessed by the Patriarch of Constantinople. In effect, however, the removal of iconoclastic books from circulation had the effect of destroying those books, especially since one would not expect the Patriarch to keep each copy of every book.
As almost a footnote, it is interesting to see that this prominent role was held by the Patriarch of Constantinople, not the Patriarch of Rome. There is, of course, a practical reason beyond the fact that the Bishop of Rome was not considered the head of the church in that day: the heart of the resistance to icons would be expected to come from the Eastern church, where just 30 years previously a similarly sized council had condemned icons as contrary to Scripture and Tradition.
Ultimately, though, this council's decree creates an easy historical explanation for the dearth of writings from the Early Church Fathers against images of Christ: they were rounded up and ultimately destroyed by those who followed the so-called Seventh Ecumenical Council. But for this council, any silence in the Early Church Fathers on this topic would have been harder to explain.