I have noticed a trend among some atheists out there, and maybe a few others, that they love to use accuse Christians that are responding in discussions of, using the No Scottsman Fallacy. Before I continue on, lets cover what it means again. Here is an example from Wiki, that was in response to a person asking if Christians are guilty of this, and I quote:
"No True Scotsman is a logical fallacy by which an individual attempts to avoid being associated with an unpleasant act by asserting that no true member of the group they belong to would do such a thing. Instead of acknowledging that some members of a group have undesirable characteristics, the fallacy tries to redefine the group to exclude them. Sentences such as "all members of X have desirable trait Y" then become tautologies, because Y becomes a requirement of membership in X."
So we fully understand what it means, so that we can reply. Usually, Christians will use a phrase somewhat like, "Well people that kill, murder, and do horrible things, are NOT Christians." You need to understand what it is being said in response to, and also understand that being a Christian actually means something in itself. We do have to know what a Christian is, to know what one is not, even if a person declares him or herself a Christian. It is a fact, that in life and history, people have always called themselves something they are not. We are not going around accusing them of the no Scottsman fallacy for that.
When I see Atheists using this tactic, and it is no more than that, just another accusation so often, I like to point it out. Jesus and the apostles showed and told what it was to be a Christian. It is not against the law of nature or something, for a human being to want to call themselves a Christian, and commit atrocities. It isn't right, but the atheist using this tactic is not being fully honest that it means something in particular to be a Christian. They would rather lump a whole group into some larger negative category for their own purposes it seems.
I feel like I am a Christian that can be fair, and add that some "members of the group" are not really acting Christ like all the time. Lets say we lower the bar, and talk about selfish people now, that aren't giving away all they have to the poor (another accusation they give to Christians sometimes). Well, Jesus and the Bible beat them to that punch. Of course if you watched them 24/7 you will find some selfish, non Christlike act. What does that prove though? Nothing, but that Jesus predicted that first and had the answer for it. The Gospel and Christianity still stand.
When something like this doesn't sit quite right, and you are getting tired of the accusations, step back and think about why their "logical fallacy" is often illogical itself, in the way they apply it. One can often easily point out the overly emotional lashing out of the atheist that is sometimes going on, that is very illogical to try and maintain and defend a certain belief. Notice the irony there, as that is something they accuse the Christians of.