This leads to my favorite discussion: can we apply post modern ideas to biblical interpretation? I.E. is it legitimate for two different people to come to the Bible and reach opposite conclusions after much prayer and study? Can the Holy Spirit lead two different people to completely opposite interpretations? Or is their only one correct interpretation of Scripture?

To the first question, I agree: G_d gave us leeway to define certain issues for ourselves (in judicious liberty), provided we do and express that definition in love and understanding humility. I should note, the Bible gives hints on most issues (even by example counts quite well enough: consider polygamy, never expressly forbidden except for kings and yet every single example of multiple wives multiplied the disasters in family life), so whether the two persons in question have consulted the Word on the subject would have a bearing.

Second, Paul was talking about general condemnation (I think), not whether or not the person is wrong. We as mature believers can have opinions on what is right and wrong, and we should be able to discuss those veiws in a manner that is uplifting and enlightening (ie, we are called to witness to unbelievers, something you can’t do and at the same time claim that its just an opinion). Love the sinner and hate the sin (and, the warning probably implies not to preach about that specific sin every time you see them)

Third, false teachers are (once proven heretically wrong via the Word) not only wrong but can contaminate the body by spreading thier false doctrine. To hold a wrong theology within the church is not good, but to allow such a one to teach it is unacceptable. The injunction not to condemn does not apply to clear heretical beliefs within the church (the Corinthians were wrong by obvious biblical standards), and it is the responsibility of the elders (or in Pauls case, as the authority over the elders) to maintain the purity of doctrine within the church.
The discussion of fruit is almost another topic entirely, relating to being perceptive (wise as serpants) about who is a good example and who you should not be spending copious amounts of time with (or take advice from, since if there is no fruit, they are not a strong christian). Fruit applies in the Jewish tradition to children, which is where I think the passage is focused; families who want to improve the fruit of their womb should look at the result of other people’s “gardening” techniques, and spend time with those who got the best results, avoiding the weed patches. The fruit example seems more introspective than prospective or outward (as in judging), since it can apply to our own lives as well (if your life is a weedpatch of sin, you need to get on your knees). But I digress.

Anyway, I basically agree with you, merely adding to the discussion for discussion’s sake. I hope someone who disagrees comes along to hang out on the comments section; its easier to define one’s postion when there is opposition.