About Logs
I was recently contemplating Jesus's sermon on judgement (Check in Luke 6, around verse 37 or so), and I was struck immediatly by three principles, when it comes to 'judging' other Christians.
1. It has to be done out of concern. We can't be "Hah! You have a speck in your eye, and I don't," the way most unbelievers seem to view us, but rather "That's a nasty speck. Can I try and get it out for you?"
2. You have to be circumspect with regard to what you are trying to correct. That's the whole point of Jesus's sermon. Chastising a gossip is obviously going to backfire if she knows you gossip too, but even if your record looks clean, don't try and fix someone's problem if you have it too! You know, "First remove the Log from your own eye so that you can see clearly to remove the speck from your brother's."
3. In the end, it's not your choice. In Jesus's example, the log-bearing hypocrite at least knows enough to ask permission before sticking his hand in his brother's eye. If a friend has a problem you think you can solve, go ahead and be crafty, or tactful, or whatever you need to get permission, but remember that the bespecked one makes the final decision.
This means that when you see a fellow Christian with an issue, there are a few things you have to do before confronting them. First, make sure you don't have the same problem, and look hard. Second, seriously consider whether or not you really are concerned with the other person's well-being. Third, find a way to show them the self-destructiveness of their ways, so that maybe they will permit your help.
Just as a totally off-topic gripe, when writing the possesive form of a name that ends with 's', it is NAME-APOSTROHPE-S! Not Jesus', but Jesus's! The lone apostrophe is only used for plurals (Seven dogs' chewtoys.)