Do not speak evil of one another, brethren. He who speaks evil of a brother and judges his brother, speaks evil of the law and judges the law. But if you judge the law you are not a doer of the law but a judge.
~ James 4:11
I've spoken poorly about my brothers and sisters in Christ before. It is wrong. Not only is it prideful, but it is downright divisive to the body of Christ. You can't build a strong body that way. If I really loved the brother/sister I was talking about, I would go to them personally and confront them about their sin in a gentle way. It is often fear on my part that keeps me from speaking truth and it's easier to just tell someone else about it than to risk a bad reaction from the person concerning. I also need to be careful not to talk about some one's sin issues under the guise of "prayer concerns" when I know in my heart I just want to spread gossip! That is incredibly deceptive. Lord, forgive me for times that I have done this! The only one to truly judge these people should be the Supreme Judge who established the laws Himself. It is not my job to go blabbing about someone else's sin issues.