Jesus never said any such thing. Paul did, in his first letter to the Corinthians. And, in fact, he didn't say that one could, but was using an extreme example as hyperbole.

1 Corinthians 13:2 (NIV): If I have the gift of prophecy and can fathom all mysteries and all knowledge, and if I have a faith that can move mountains, but have not love, I am nothing.