I don’t think you’ll find that sentence in Shakespeare. It was said by Henry II about Thomas a Becket, who was subsequently murdered as he said Mass.
The only play that about the story that I know of is one by T.S. Eliot. Title escapes me righ now.
“Murder in the Cathedral”
I have another quote, more or less, this time from Dan Rather:
“Fake, but correct.”
Thanks for the correction.