Suetonius, Life of Claudius 42
The Emperor Claudius died on this day in AD 54, allegedly poisoned with mushrooms administered by the dastardly Agrippina. But we had Latin yesterday here on aleator classicus, so it must be Greek today; conveniently enough the Emperor who wrote prolifically in Greek also quoted Homer often, so here is a passage from Suetonius explaining how his Guard’s daily watchword was sometimes a Homeric one.
quotiens quidem hostem vel insidiatorem ultus esset, excubitori tribuno signum de more poscenti non temere aliud dedit quam
ἄνδρ᾽ ἀπαμύνασθαι, ὅτε τις πρότερος χαλεπήνῇ.
On those occasions when he had taken vengeance on an enemy or conspirator, he would generally give this line when the Tribune of the Guard asked for the usual watchword:
Ward off the man who is the first to show his anger.
The line is used twice in Homer: at Iliad 24.369, when a disguised Hermes is advising Priam (who is taking a great risk carrying treasure across the Trojan plain), and Odyssey 21.133, where Telemachus is lamenting how cowardly he is.