This is easily illustrated in both words' cases.
Jews for Jesus, whom I have much respect for as a Christian (and whom we've gladly had teach at our Jesus People USA community), is labeled a "cult" by various Jewish organizations and even charged with brainwashing. Evangelicals would quickly object. Yet we in turn slap the term "cult" on groups such as the Mormons (see acquaintance John Smulo's blog for his critique on a specific example). I don't suggest that Christians are wrong to critique Mormonism; far from it. But the use of the word "cult" prevents any sort of mutually-engaging conversation, and practically assures those so labeled will respond with hostility.
As Smulo rather testily observes,
Is it not hypocritical that we would use confrontational tactics and hateful propaganda to preach a loving God!? Let me slap you in the face and then tell you about how loving our God is!!! Do you think anyone in their right mind would listen!?
If I were merely a cynical soul (well, sometimes I am, but we won't go there now), I would end with a biting comment. Instead, as a lover of Christ, I am forced to offer more than that.
I beg my fellow believers to take a long, hard look at language being used as a club. Particularly when one word is so emotionally loaded that it becomes literally an eraser -- a way of denying the humanity of those it allegedly describes -- that word is no longer useful to the Christian. I choose "useful" in the context of love, love first and foremost.
But what about a person or persons who teaches what is unchristian or does evil?
Why not, then, describe what they teach or what they do? For instance, the individuals who rammed two airplanes into the twin towers, another into the Pentagon, and another into a Pennsylvania field, could we not by simply describing what they did prove they did evil? Why must we shorten it into a cartoonish, non-descriptive word such as "terrorist"?
Psychologically, such illicit linguistic shortcuts offer us a way to explain evil. But such an explanation is in itself intrinsically evil, because it allows us to externalize evil onto the "other guy."
These ideas applied to the word "cult" are not new, and sociologists such as David Bromley, Anson Shupe, Dick Richardson and others have dealt with their religious / social ramifications. But as we watch and listen to the west's very dubious use of words such as "freedom" to describe the rationale for bombing Lebanon and invading Iraq, the term "terrorist" takes on an almost doubly sinister meaning. Namely, there are others standing in the rubble of what used to be "the Paris of the Middle East" and they have quite a different set of villians to call terrorists. The ruins of Beirut are, like the twin towers, evidence that seems to an unbiased observer the incontrovertible sign of evil.
I still remember the horror I felt when I first heard (then saw) the fall of the twin towers. It was indeed a successful blow against my, and our, self-identity as Americans. I was angry, I wept, I prayed agonizing imprecatory prayers!
In the end, we will have done to us what we do unto others. We, to them, are the terrorists. We, to them, are the cultists. Why? Because we threaten the very basis for their civilization, the basis of their own understanding. Is that the feeling we want to leave throughout entire regions of the world? (And I'm thinking of the Middle East in particular.) If we make no attempt to understand, to actually see through their eyes the world they (and we!) inhabit, how can we expect any more than vitriolic verbal attack or even violent assaults?
Will all human beings, no matter how bent on violence or at least willful deception for gain, respond to gentle and respectful attempts at dialogue? Absurd. They certainly will not. Yet this does not let us off the hook. We are Christians, after all. We are called to forgive "seventy times seven" and go the second mile and to love our enemies. How does that unpack in real life? Perhaps it ends with us imitating Christ in his sufferings past any point we ever thought we would or could. Perhaps not. But it certianly confronts us with our own lack of belief in what and who Jesus actually was.
The time has come to describe people as human, even when they do terrible things. That, too, is a definition of humanity we would rather wasn't universally true. Why? Because, despite our having a hard time grasping the fact, there's enough evil to go round.
The universal nature of human evil, after all, led to a certain incident near the city dump outside Jerusalem two thousand years ago. From a Christian perspective, one can really only use the term "terrorist" when applying it first and foremost to one's own self.