Peter "stood condemned" because his "conduct was not in step with the truth of the gospel". Because of the actions of Peter and the other Jews, "even Barnabas was led astray".
Should we just accept anything we hear in church as the truth? How can we measure or verify what we hear? Should we just follow our betters without question?
I think all we can do, is what the Berean's did. Search the scriptures daily, to see if these things are so.