Dylan Pahman of the Acton Institute has a provocative post on St John Damascus. Pahman argues that we can look to the example and explicit teaching of St John as a defense on the limits of government relative to both communities (specifically to the Church but I think the point is more broadly applicable) and personal conscience.
For St. John of Damascus and all of the Orthodox with him, there was a clear limit to government power: it could not intrude uninvited into the realm of the Church and could not command its subjects to defy what their consciences knew to be the truth. Any power it had was given from above, and thus could not be absolute. In such circumstances, he found himself “[c]ompelled to speak by a fear that cannot be borne.” And his effort for the sake of truth and freedom proved invaluable. The theology of the Seventh Ecumenical Council in 787 (Nicaea II) is largely dependent upon his three treatises.
Even after the brief period of peace in which the council was called, the iconoclasts again regained power and the persecution continued, only ending in 843 on what is known in the Orthodox Church as the Triumph of Orthodoxy. St. John of Damascus reposed sometime before 750, having never seen the fruits of his labors in the flesh. Yet, his example is one of hope to many who have contended for freedom and faith from his own time to the present day. And for that I, at least, commemorate him today and commend the same to any others who treasure faith and freedom in our own time.
You can read the whole essay here.