History of the Peloponnesian War

Thus much was said to the Argives and their confederates. But the Lacedaemonians encouraged one another both of themselves and also by the manner of their discipline in the war, taking encouragement, being valiant men, by the commemoration of what they already knew; as being well acquainted that a long actual experience conferred more to their safety than any short verbal exhortation, though never so well delivered.