History of the Peloponnesian War

But the Athenians would by no means put the matter to judgment, but meant with all the speed they could make to send an army against it, being angry at the heart that it should come to this pass, that even islanders durst revolt and trust to the unprofitable help of the strength of the Lacedaemonians by land.

Besides, touching [the time of] the revolt, the Athenians had more truth on their side than themselves alleged; for the revolt of the Scionaeans was after the truce two days. Whereupon, by the advice of Cleon, they made a decree to take them by force and to put them all to the sword. And, forbearing war in all places else, they prepared themselves only for that.