Originally Posted by semtex

He can't, if he's an Evangelical Christian, emphasis on the 'evangelical'. The whole premise of evangelism is to spread the word and convert others. And many hardcore evangelicals reason that this duty extends to speaking up where and when they see wrongdoing (versus turning a blind eye and just ignoring it). Not saying I agree with this approach or support it. I'm just explaining the mindset -- the ideology posits a duty to meddle with others, be it by going to door to door, preaching on the sidewalk, denouncing people in 'sinful' forum threads, whatever.