Who said this quote Everything will be okay in the end. If it's not okay it's not the end?

John Lennon, but at the moment it's made popular by the movie "The Best Exotic Marigold Hotel"

Paolo Coelho - Not John Lennon. He's a Brazilian writer, I believe.

I'm not convinced. Mr. Coelho quoted many other people himself. Translating and using quotes doesn't mean they are yours. In '11 minutes' you'll find him quoting the entire lyrics of a song by 'The Brothers Four', which eventually are based on verse from the Bible. Yet they figure as 'Quotes by Paolo Coelho' in the internet.

I first coined this phrase in 1964 in Miami, Florida, well before John Lennon is said to have originated it. I said it as a joke, but it subsequently gained popularity and later was attributed to John Lennon. This did not originate with Mr. Lennon, but with me.