1 Cor. 9:20-22

Notice that Paul deliberately refused to customize his message or adjust his delivery to suit the Corinthian's philosophical bent or their cultural tastes. When he says later in the epistle, "To the Jews I became a Jew... to those without the law, as without law... to the weak I became as weak, that I might win the weak. I have become all things things to all men, that I might by all means save some" (1 Cor. 9:20-22), he was describing how he made himself a servant to all (v. 19) and the fellow of those whom he was trying to reach. In other words, he avoided making himself a stumbling block. He was not saying he adapted the gospel message (which he plainly said is a stumbling block- 1:23). He did not adopt methods to suit the taste of a worldly culture.

Paul had no thought of catering to a particular generation's preferences, and he used no gimmicks as attention-getters. Whatever antonym you can think of for the word showmanship would probably be a good description of Paul's style of public ministry. He wanted to make it clear to everyone (including the Corinthian converts themselves) that lives and hearts are renewed by means of the Word of God and nothing else. That way they would begin to understand and appreciate the power of the gospel message. 

-from The Truth War by John MacArthur