26. Amīr al-mu’minīn, peace be upon him, said: Whenever a person conceals a thing in his heart it manifests itself through unintentional words from his tongue and (in) the expressions of his face. 
 The things which a man wants to conceal from others do come out through his tongue sometime or another, and his effort at concealment is unsuccessful. This is because although the far-sighted mind desires to keep them concealed yet sometimes it gets entangled in some more important matter and becomes careless on this score when the concealed thing comes out in words through his tongue. When the mind becomes attentive, it is not possible to undo the matter just as an arrow cannot be got back after shooting. Even if this is not the case and mind is fully cautious and attentive, the thing cannot remain concealed because the lines of the face are indicative of mental feelings and reflect the heart's emotions, and consequently redness of face can easily point out to the sense of shame, and its yellowness fear.