I think Christians lie because they are taught to do so by their pastors and religious leaders. The only thing that matters, it seems, are the beliefs held by a particular tradition.
These beliefs are engrained in the Christian, made infalliable by circular reasoning, and then solidified by the warning from the pastor that one's faith absolutely depends on the veracity of these claims.
Unfortunately for the dishonest Chrisitan, nothing is infalliable, and in fact honest reasoning requires the subject to be falliable so one can change one's mind if one is wrong. So, to defend these precious doctrines to oneself and others, the Christian must lie. And we see Christians lie about Greek and Hebrew to support various doctrines; lie about science to support creationism; lie about the faith of others fir simple disagreement; lie about the nature of other religions --- it is truly limitless.
When did it become OK for Christians to practice such open hatred for the truth, and hypocritically claim to be the bearers of it?
It is abundantly obvious that it doesn't have to be this way. Honesty will strengthen faith. If one's only desire is for the truth of the matter, especially if it challenges one's faith, so much the better for intellect and faith.
Really we are not calling all christians liars it certainly reads that way.
I would say that most christians I know would not even call others liars let alone there own kind.
I believe it is christian to judge not lest ye be judged. I am done with this thread there is no point to it.