Individuals fall prey to illness, but the contagions that infect a civilisation are ideas. In the 8^th and 9^th centuries a Byzantine civilisation reeling before the onslaught of expansionist Islam was simultaneously torn apart by a controversy that might seem ridiculously abstruse from our vantage point: whether or not it was permissible to paint images of Christ and the saints. But to conclude that the Byzantines were wasting energy desperately needed for the defence of the empire is to make the mistake of judging them with the myopic gaze of the 21^st century. Icons expressed the civilisational core of Byzantium, therefore their creation or destruction was vital to how New Rome saw itself.

An icon (pace Bill Gates and sloppy journalists writing about mediacrities) is an image of Jesus, Mary, the saints or angels, generally painted on wood and richly coloured, often using gold leaf. Go into any Orthodox church today and the first thing that will strike you will be the glorious icons, glittering in the candlelight.

But in 726 the Emperor Leo III removed an image of Christ from above the doors to the imperial palace. Even that produced riots and deaths, for Byzantium saw itself as under the protection of Jesus. However, the emperor was not to be dissuaded and in 730 Leo took action, deposing the patriarch of Constantinople and ordering the removal or destruction of all icons from his city. All resistance was suppressed, violently. To judge how effective his policy was we simply have to note the almost complete lack of surviving icons from before the 8^th century.

Why did Leo, on his own initiative, plunge his empire into what was virtually civil war, with the monasteries acting as an underground, hiding and protecting icons from the imperial troops? Part of the answer lies in the Byzantines’ struggle against Islam. As with their Muslim adversaries, the Byzantines saw success or failure as marks of God’s favour or disfavour. Thus their defeats by the aggressively iconoclastic Muslims lead some Byzantines to search for reasons why God had turned his face from them. They found a reason in the belief that the veneration of icons was idolatrous, in contravention to the second commandment forbidding graven images, and in the conclusion that since an icon only showed Christ’s human form it did violence to his nature as both fully human and fully divine.

Icons having been forbidden solely on imperial authority, Leo’s son and successor, Constantine V, decided to go for some ecclesiastical back up. He called a council of the church in 754, making sure that it consisted of bishops upon whom he could rely and notably excluding from the proceedings the Pope, and the Patriarchs of Alexandria, Antioch and Jerusalem. Sure enough, the meeting – later dubbed a robber council – duly rubber stamped the emperors’ actions.

However, the iconodules (those who venerate icons), were now mobilised. Their resistance centred on the monasteries and they found a spokesman in St John of Damascus, who though a Christian held the post of chief councillor to the Muslim Ummayad rulers of his city in Syria. Safely out of the emperor’s reach (or so he thought) John began to write in defence of icons, basing his case on the proposal that icons were not idols but rather depicted the sanctity of the figure portrayed as a reflection in a pool of water. He further pointed out that iconographers were only painting what God himself had done: become flesh and blood in the person of Christ. Therefore, to follow the iconoclasts’ logic, the first and greatest idolator was God himself.

The story goes that the emperor, unable to get at John directly, forged a letter purporting to show John offering to betray Damascus to the Byzantines. An unamused Caliph had John’s writing hand cut off.

The controversy continued for over a century, going through three more councils, each reversing the policy of the one previously, a number of emperors and two empresses. It was the women who decided matters in the end. The Empress Irene was the first to reverse the iconoclast policy of her predescessors, and in 843 the Empress Theodore proclaimed the restoration of icons. Since then the first Sunday of Lent has been celebrated as the feast of the triumph of Orthodoxy.

Who was right? It’s not for us to say. But go into an Orthodox church and look at the icons behind their flickering curtains of light. That glow you see. Is it a reflection, or an intimation of heaven?