From time to time I receive chastisements from people who tell me that the Buddha wouldn’t care about being misquoted. How they know this, of course, is a mystery. Perhaps they have psychic powers that allow them to communicate with the dead. They certainly don’t seem to get their knowledge from the Buddhist scriptures, where one of the few things that really seemed to annoy the Buddha (besides noisy monks) was having words put into his mouth.
“Monks, these two slander the Tathāgata [a synonym for "Buddha"]. Which two? He who explains what was not said or spoken by the Tathagata as said or spoken by the Tathagata. And he who explains what was said or spoken by the Tathagata as not said or spoken by the Tathagata. These are two who slander the Tathagata.”
Woodward (Gradual Sayings, Volume I, page 54) translates this same passage as:
Monks, these two misrepresent the Tathāgata. What two?
He who proclaims, as utterances on the Tathāgata, what he never said or uttered, and he who denies what was said or uttered by the Tathāgata. These are the two.
And in case you’re interested, here it is in Pali:
Dveme bhikkhave tathāgataṃ abbhācikkhanti. Katame dve ? Yo ca abhāsitaṃ alapitaṃ tathāgatena bhāsitaṃ lapitaṃ tathāgatenāti dīpeti, yo ca bhāsitaṃ lapitaṃ tathāgatena abhāsitaṃ alapitaṃ tathāgatenāti dīpeti. Ime kho bhikkhave dve tathāgataṃ abbhācikkhantīti.
In other words, according to the scriptures, the Buddha really, really didn’t like Fake Buddha Quotes.