Hadith 59
Sayyiduna Ali (may Allah be pleased with him) says: The Messenger of Allah (peace and blessings be upon him) said: "I do not fear for my Ummah from any believer or polytheist, because faith will prevent the believer from excess, and disbelief will destroy the polytheist. But I fear among you the hypocrite who is a scholar only with his tongue; he will say things that you recognize, but he will act in a way that you consider evil."