Philostorgius, Ecclesiastical history
“ And when the emperor asked him why he alone of all kept silence, Leontius answered thus : "I am astonished that you, who are set over matters of one kind, to administer them, should take in hand the administration of others which are distinct from them : and that when the care of military and civil matters has been intrusted to you, you should dictate to bishops in matters which appertain to the office of a bishop alone." ”
