I see this trend, not only in Christian circles, but also in politics, as well as other areas. It is under the guise of 'warning' people about the bad guy, or the deceiver.
In apologetics, there are some rules. One of them is that the apologist, or Christian who is defending the faith, does not personally attack the opponent.
I watched a debate one time, between Christopher Hitchens and Dinesh D'Souza. It was interesting in that the rules were being followed fairly well, at least at the beginning. Eventually though, I noticed the Atheist, Christopher Hitchens, attacking the person of his opponent, Dinesh.
The Bible is very clear that we are not to speak evil of someone, and that means, even if he or she is doing wrong. I do understand that we need to 'warn' people, at times, of someone who has come into the church who will end up leading people astray. There is a way to approach this and still be God honoring.
We actually had a time in our church where we had to address a situation with a false teacher. Many were flocking to this 'church' or whatever it was. Some even left us to join this 'church'. We listened to some messages given by the pastor or whoever it was that ran this group. He believed in 'antinomianism' which is a belief that you can do whatever you want to and still be a genuine Christian. Our pastor got up and explained what was going on to the people. I don't know how many more would have left if that situation did not get taken care of.
I also know that many will disagree with me on this issue. But, here is my concern; Could we be taking advantage of a situation that our sinful hearts are really enjoying, while we say we are really trying to protect the church?
We have indwelling sin and if we are not careful, the Enemy of our souls will tempt us to be prideful. What that looks like, many times, is attacking someone with our words. We need to address situations, but to attack the person and resort to name calling is uncalled for. We will give an account to God on how we treated other people, whether they are false teachers, or crooked politicians.
Before I came to Christ, I loved to gossip about people. I loved listening to gossip as well as creating it myself. But all that changed one day, when God convicted me of my sin. I was not loving people when I slandered them. Before my heart was changed, I would even gossip and slander my friends! When my heart was filled with God's love, I stopped doing that and had a different perspective in life.
Here is an example of what we should not be doing: Obama is a scumbag. He just wants to rip people off.
Here is an example of how we can present our side, and do it graciously; From what I can tell, Obama has a philosophy that says that rich people in America today should be made to pay back those who were ripped up during the early years of our country (Source: America; Imagine The World Without Her).
The first example is name calling and making a claim that is based upon an opinion. The second example is explaining what Obama believes in and practices that is harmful to our nation.
Here ia an example of what we should not be doing; "Joyce Meyer is a false teacher". This is just an opinion that sounds like people who are jumping on a bandwagon want to say to impress others of their knowledge of a false teacher. There are no quotes given or resources from her pages that tell what it is that she is doing wrong to show that she is a false teacher, if she is one.
Here is an example of how we can expose a false teaching; "Rob Bell is a professing Christian who does not believe Christians are supposed to be doing evangelism." This is evidenced in his book, 'Velvet Elvis" and also on his video, 'The Bullhorn Guy". Notice that we do not have to attack Rob Bell's character here. We do not have to make it a point that he is a 'false teacher'. The point is not to criticize the person himself, but to point to what the person believes in and actually teaches.
One last thing; we do not have to make connections for people, most of the time. What we want to do is to present the facts and let them speak for themselves. We don't have to resort to name calling and we need to let the Holy Spirit help us to learn to separate the truth from the lies.
If we spent more time teaching/training people how to be discerning, and how to discern the word of God for themselves, we would not have to write posts 'warning' people about those false teachers. If we have a friend or loved one who embraces the teachings of someone in error, we should ask them questions about why they like sitting under that particular teacher. Then we can point out what the false teacher is teaching (from what we already know, not from someone else's speculation on the person).
In the Bible, where false teachers are mentioned and warned about, the person was warning the group of believers about the person who had crept into their midst. They were marked because of what they had done. Paul and Peter did not speculate or listen to rumors about these guys. They knew exactly what the bad guys were standing up for and trying to infiltrate the church with.
Please be careful to know the facts for yourselves when talking about someone, especially on Facebook or Twitter. If they are a known false teacher, with teachings that are truly false, and you have evidence on it, then carefully present the facts, but never attack the person. Remember, whatever measure we dole out to others will be the measurement God will use against us. If we do not show mercy, God will not show us mercy. Also, remember the spiritual weapon of prayer. God can do things in the hearts of people that we can't even imagine.
"Now to him who is able to do far more abundantly than all that we ask or think,according to the power at work within us, to him be glory in the church and in Christ Jesus throughout all generations, forever and ever. Amen." Ephesians 3:20, 21 ESV