It is also likely that Paul is trying to separate himself from the typical traveling teacher, the sophist who used his oration skills to gain popularity and wealth. In this case, Paul contrasts his motives with those of the sophists or other philosophical mountebanks. Like snake-oil salesmen in the old west, the traveling teacher was a well known character int he Greco-Roman world. Bruce Winter suggested that Paul was distancing himself “from the habits of the sophists, who entered the cities of the empire with great pomp in order to gain an audience and disciples for their teaching.” (Cited by Green, 112.) Gene Green also cites Dio Chrysostom as an example of a philosopher who set himself up as a model to be followed (in contrast to other philosophers and sophists.)
But to find a man who in plain terms and without guile speaks his mind with frankness, and neither for the sake of reputation nor for gain makes false pretensions, but out of good will and concern for his fellow- man stands ready, if need be, to submit to ridicule and to the disorder and the uproar of the mob—to find such a man as that is not easy, but rather the good fortune of a very lucky city, so great is the dearth of noble, independent souls and such the abundance of toadies [flatterers], mountebanks, and sophists. (Dio Chrysostom , 32.11)
One way to define yourself is to describe what you are not. For example, I might say that I am a Christian, but not like those guys on TV, or those people that protest at military funerals, or like those people that predict the end of the world, etc. My intention is to define accurately what I do believe by contrasting myself to more well known “characters” from our culture. Paul does not want to be seen as a sophist anymore than I want to be seen as the typical “nutter” Christian, the contemporary characterization which is not at all accurate.