Are there any true scotsmen who are also true christians?

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.