Late 14th-early 15th century icon illustrating the "Triumph of Orthodoxy" under the Byzantine empress Theodora over iconoclasm in 843. (National Icon Collection 18, British Museum). Theodora was regarded as an iconodule.
The controversy was instigated by Byzantine Emperor Leo III in 726, when he ordered the removal of the image of Christ above the Chalke Gate of the imperial palace in Constantinople. A wider prohibition of icons followed in 730. St. John of Damascus argued successfully that to prohibit the use of icons was tantamount to denying the incarnation, the presence of the Word of God in the material world. Icons reminded the church of the physicality of God as manifested in Jesus Christ.