Xenophon Hellenica 5.4.13

[13]
  When the Lacedaemonians learned of these events, they put to death the governor who had abandoned the Acropolis instead of waiting for the relief force, and called out the ban against the Thebans. Now Agesilaus said that it was more than forty years since he had come of military age, and pointed out that just as other men of his age were no longer bound to serve outside their own country, so the same law applied to kings also. He, then, on this plea would not undertake the campaign. It was not, however, for this reason that he stayed at home, but because he well knew that if he was in command the citizens would say that Agesilaus was making trouble for the state in order that he might give assistance to tyrants. Therefore he let them decide as they would about this matter.