Barber, "but in an age so highly conscious of symbolic acts", took on a greater political import. The confusion at Sutri may have been accidental, but Frederick also took offence at a mural in the Lateran of his predecessor Luthar which described the Emperor as a liegeman of the Pope. The painting was inscribed with the verse Indignant, Barbarossa made a "friendly reproach" to the Pope. In a letter to a German bishop, he explained, "it began with a picture. The picture became an inscription. The inscription seeks to become an authoritative utterance. We shall not endure it, we shall not submit to it." Adrian told Barbarossa he would have it removed, "lest so trifling a matter might afford the greatest men in the world an occasion for dispute and discord. In the event, Adrian did not, and by 1158 Imperial commentators were describing the matter of the painting and its inscription as the fundamental cause of the dispute between Pope and Emperor. Adrian, says Freed, was "perplexed" at the Emperor's refusal to offer him squire service: he "dismounted and seated himself on a folding stool". Barbarossa, if he wished to be crowned, had limited options against the Pope. He took advice from councillors based on records of "the more ancient princes and especially those who had come with King Lothar to Pope Innocent". An entire day was spent inspecting both "old documents", and hearing from those of his entourage who had been present at the 1131 ceremony. The Pope's party saw this as a sign of aggression, and deserted Adrian for the security of a nearby castle. Imperial coronation, 1155 The Emperor was, though, eventually persuaded, performed the necessary services. He was eventually crowned in Nepi on 18 June. Peace was maintained at Nepi, however, and both Pope and Emperor dined together, wearing their crowns in a joint celebration of the Feast of Saints Peter and Paul. There was much rejoicing, and contemporaries went so far as to proclaim that "a single state had been created from two princely courts". Ullmann, on the other hand, argues that, not only was the Emperor's power clearly derivative of the Pope but that Adrian himself had further diluted it in his rendition of the coronation ceremony. Nor was there an official enthronement for the new emperor. This ceremony, says Sayers, was arguably a new version of the traditional one, which now "highlight[ed]