History of the Peloponnesian War
Thucydides
Thucydides. The history of the Peloponnesian War, Volume 1-2. Dale, Henry, translator. London: Heinemann and Henry G. Bohn, 1851-1852.
And yet if they appear to be serviceable to you now, much more did we and the rest of the Greeks then, when you were in greater danger. For now you are yourselves attacking others, and the objects of their fear; but at that crisis, when the barbarian was bringing slavery on all, these Thebans were on his side And it is but just, that against our present misdeed—if we have really done amiss—you should set the zeal we showed then;
and you will find it greater [*]( Literally, the greater opposed to the less. ) than the fault to which it is opposed, and exhibited at those critical times when it was a rare thing for any of the Greeks to oppose his courage to the power of Xerxes; and therefore those were the more commended who did not in safety act for their own interest with regard to his invasion, but were willing to dare with dangers the better part.