Regum et imperatorum apophthegmata

Plutarch

Plutarch. Moralia, Vol. III. Babbitt, Frank Cole, translator. Cambridge, MA: Harvard University Press; London: William Heinemann Ltd., 1931 (printing).

Idanthyrsus, the king of the Scythians, against whom Darius crossed the Danube, tried to persuade the despots of the lonians to break up the bridge that spanned the river, and then withdraw. But when they were not willing to do so because of their plighted word to Darius, he called them good slaves who would never run away. [*](Cf. Herodotus, iv. 142.)