My witness is my poverty
You will not easily find another like me, and therefore I would advise you to spare me. I dare say that you may feel out of temper (like a person who is suddenly awakened from sleep), and you think that you might easily strike me dead as Anytus advises, and then you would sleep on for the remainder of your lives, unless God in his care of you sent you another gadfly.
When I say that I am given to you by God, the proof of my mission is this:—if I had been like other men, I should not have neglected all my own concerns or patiently seen the neglect of them during all these years, and have been doing yours, coming to you individually like a father or elder brother, exhorting you to regard virtue; such conduct, I say, would be unlike human nature. If I had gained anything, or if my exhortations had been paid, there would have been some sense in my doing so; but now, as you will perceive, not even the impudence of my accusers dares to say that I have ever exacted or sought pay of any one; of that they have no witness.