It has been speculated that is was, even by the Byzantines themselves. The ninth-century (iconophile) historian Theophanes the Confessor, for example, claimed that Leo III's edict was inspired by one issued a few years earlier by Caliph Yazid II. It seems likely, however, that the Muslim prohibition on sacred images was only one of several influences on Iconoclasm.

Misgivings about the veneration of images were implicit in the works of several important theologians (e.g. Eusebius of Caesarea), and there seems to have been a continuous line of thought, going back to late antique polemics against polytheism, that regarded figural representation of Jesus and the saints as something akin to idolatry.

Although the disasters of the early eighth century may have the proximate cause that pushed misgivings into condemnation, social and political factors were also at play. Some historians posit that Leo and his successors wished to confiscate the wealth of the monasteries, and so prodded the monks into opposition to the imperial will. Others suggest that iconoclasm was nothing more or less than a means of asserting imperial power, or represented a movement of the urban clergy against the power and influence of non-urban monks and holy men.