Hesiod. Works and Days. (Lines 267-273).
The eye of Zeus, seeing all and understanding all, beholds these things too, if so he will, and fails not to mark what sort of justice is this that the city keeps within it. Now, therefore, may neither I myself be righteous among men, nor my son -- for then it is a bad thing to be righteous -- if indeed the unrighteous shall have the greater right. But I think that all-wise Zeus will not yet bring that to pass.