- Iconoclasm was rejected by the Western church. In 745 Constantine V banned the worship of icons. The Roman church believed this doctrine to be heretical and still embraced the practice. This decision began a temporary divergence in orthodoxy between the Eastern church and Western church that, despite its eventual reconciliation, would lead the two churches to drift away from and eventually sever ties with each other.

- Iconoclasm formally ended in the Byzantine church at the second council of Nicaea. This council was convened by Empress Irene in 787. The council declared iconoclasm heretical and this decision was accepted by the Catholic church as well as the Eastern church. They determined that worship of saints through their icons was not icon worship and that the Biblical proscription on icon worship applied strictly to the worship of the icon as itself. According to Chris Wickham, the second council of Nicaea is the foundation of the liturgical practices of Orthodox Christianity.

- There were, however, those who disputed these findings in the West. In *Libri Carolini*, Theodulf of Orleans condemned the veneration of icons as supported by Nicaea. The complaint made is that the distinction between worship of a saint through an icon and worship of that icon itself was too fine. The synod of Frankfurt (794) was formed with the purpose of rejecting the rulings made at the second council of Nicaea. However, while the synod of Frankfurt argued against the theological basis of the decision of the second council of Nicaea, they still rejected the doctrine of iconoclasm.

- Heinrich Fichtenau claims that while there were real theological differences between the Byzantine church and the Carolingian church, the reason for the writing of the *Libri Carolini* and convening the synod of Frankfurt was to elevate the political position of Charlemagne, who was not invited to Nicaea, to be equal to the Byzantine emperor.