Thucydides, History of the Peloponnesian War
Benjamin Jowett, Ed.

92. How far these plans are executed, and with how much speed and energy, Lacedaemonians, depends on you; for I am confident that they are practicable, and I am not likely to be mistaken. [2] 'You ought not in fairness to think the worse of me because, having been once distinguished¹ as a lover of my country, I now cast in my lot with her worst foes and attack her with all my might; [3] or suspect that I speak only with the eagerness of an exile. An exile I am indeed; I have lost an ungrateful country, but I have not lost the power of doing you service, if you will listen to me. [4] The true enemies of my country are not those who, like you, have injured her in open war, but those who have compelled her friends to become her enemies. I love Athens, not in so far as I am wronged by her, but in so far as I once enjoyed the privileges of a citizen. The country which I am attacking is no longer mine, but a lost country which I am seeking to regain. [5] He is the true patriot, not who, when unjustly exiled, abstains from attacking his country, but who in the warmth of his affection seeks to recover her without regard to the means. I desire therefore that you, Lacedaemonians, will use me without scruple in any service however difficult or dangerous, remembering that, according to the familiar saying, ‘the more harm I did you as an enemy, the more good can I do you as a friend.’ For I know the secrets of the Athenians, while I could only guess at yours. Remember the immense importance of your present decision, and do not hesitate to send an expedition to Sicily and Attica. By despatching a fraction of your forces to co-operate in Sicily you may save great interests, and may overthrow the Athenian power once and for ever. And so henceforward you may dwell safely yourselves and be leaders of all Hellas, which will follow you, not upon compulsion, but from affection.'