Beware from destroying your manners and changing them, maintain one tongue. A man should control his tongue because the tongue is obstinate with its master. By Allāh, I do not find that fear of Allāh benefits a man who practises it unless he controls his tongue. Certainly the tongue of a believer is at the back of his heart while the heart of a hypocrite is at the back of his tongue; because, when a believer intends to say anything, he thinks it over in his mind. If it is good he discloses it, but if it is bad he lets it remain concealed. While a hypocrite speaks whatever comes to his tongue, without knowing what is in his favour and what goes against him.