The stpry (sic) of the woman taken in audultery is not < MilitantJain > 2015-07-30 08:27found in John until the 10th century. Google it.
Have Christians lied throughout history to promote their faith?
No. We haven't.
I took the opportunity to "google it" as the poster suggested and found the answer on good old WIKIPEDIA.
The story of the Adultress (known as a pericope) is found in its entirety in the Codex Fuldensis, dated positively to AD 546. That already makes the claim by the poster off by 4 centuries. The Codex Bezae also contains the pericope, and it's dated a bit earlier than Fuldensis.
There are possible references to it in the earliest Greek manuscripts. Also, one of the Greek Church Fathers, Didymus, mentioned the pericope as being found in copies of the Gospel dating to the early 4th Century.
Because of the care taken by copyists and the number of existing manuscripts that still survive, it stands as a testimony that Christians have tried to preserve the Bible and present it as completely as possible.
Atheists need to check their own sources first, and examine them with the same critical eye that they use against believers. It's a fault that few of them seem to be able to overcome.