Bismillah
Wael, you must have read:
"And verily, <b>among them is a party who distort the Book with their tongues (as they read), so that you may think it is from the Book, but it is not from the Book, and they say</b>:
"This is from Allah," but it is not from Allah; and they speak a lie against Allah while they know it." (Quran 78). Mind you that this Ayah is a part of a set starting with describing what some of the people of scriptures are up to or do as in:
"Among the People of the Scripture is he who, if entrusted with a Cantar (a great amount of wealth, etc.), will readily pay it back; and among them there is he who, if entrusted with a single silver coin, will not repay it unless you constantly stand demanding, because they say: "There is no blame on us to betray and take the properties of the illiterates (Arabs)." But they tell a lie against Allah while they know it." (Quran 3: 75)
Wael, what is really important for all of us to be aware of is that without them realising, they are turning themselves into tools to prove more and more how Quran is from Allah. The description of the Ayah fits this situation. Sobhan Allah wa Allah u Akbar.