Lying for Jesus happens quite a bit as some people think falsifying information is acceptable if that 'brings people to Jesus'.
Christian deceit in the ancient world
Lying for Jesus has an ancient and disrespectful pedigree, dating back at least as far as the Gospels, for example Matthew 27:51 and subsequent gives a series of spectacular and improbable supposed events around the Crucifixion. Neither other gospel writers not historians of the time noticed. The veil of the temple was torn, an earthquake happened, dead men/women rose from their graves, there was darkness for several hours, see Matthew 27:51. And somehow nobody else recorded all that. Below is a quotation from Thomas Paine.
The writer of the book of Matthew should have told us who the saints were that came to life again and went into the city, and what became of them afterwards, and who it was that saw them - for he is not hardy enough to say that he saw them himself - whether they came fully dressed and where they got their dresses; whether they went to their former habitation and reclaimed their wives, their husband and their property, and how they were received, whether they entered ejectments for the recovery of their possessions or whether they died again, or went back to their graves alive and buried themselves. Strange indeed that an army of saints should return to life and nobody knew who they were, or who it was that saw them, and that not a word more should be said upon the subject, nor these saints have anything to tell us! Atheists on Twitter don't think it's very reasonable either, see Happy Easter! Anyone actually read this thing?. The dead men walking may have been Hallucinations by severely stressed Christians while their Lord was dying. Still all those other remarkable and otherwise unnoticed events look more like deliberate deceit.
Slightly later was the Testimonium Flavianum, supposedly by Jewish historian Josephus though only a Christian could have written it. So a Christian lied and pretended Josephus wrote it.
About this time there lived Jesus, a wise man, if indeed one ought to call him a man. For he was one who wrought surprising feats and as a teacher of such people as accept the truth gladly. He won over many Jews and many of the Greeks. He was the Messiah. When Pilate, upon hearing him accused by men of the highest standing amongst us, had condemned him to be crucified, those who had in the first place come to love him did not give up their affection for him. On the third day he appeared to them restored to life, for the prophets of God had prophesied these and countless other marvellous things about him. And the tribe of the Christians, so called after him, has still to this day not disappeared. 
Different Christisan sects are also quite often prepared to distort the position of other Christians whom they consider heretics. Naturally very many different types of Christians are totally convinced theirs is the only true way to Jesus or theirs is the only true Church of Christ etc etc.
More recent Christian deceit
A book has been written, "Liars for Jesus" reviewed on RationalWiki, this book deals mainly with American Christians claiming the United States is more of a Christian than is really the case.
Dishonesty by Creationists, particularly Young Earth Creationists is well known and documented elsewhere, even at least one Christian acknowledges that it happens. YEC dishonesty simply demonstrates the lack of honest evidence for the YEC position. 
A Christian pastor of all people set out to discredit atheists by pretending to be an atheist, (Christians are forbidden to deny their faith). This pastor posted utterly repulsive immoral material which he hoped others would take as atheist views. 
- How can you tell the difference between Christianity and an abusive husband or boyfriend?
- How can you tell the difference between Christianity and a scam?