Imam Ali (as), in his will to his son Muhammad b. Hanafiyyah, said: 'O my son, do not say that which you do not know, and, at the same time, do not say everything that you do know, for Allah has enjoined certain duties on each and everyone of your limbs, which He will use to testify against you on the Day of Judgement, and He will ask you concerning them, as to how you heeded their counsel, their admonition, their warnings, and how you refined them, and He has not left them to wander aimlessly.
Allah, Mighty and Exalted, has said: 'And do not follow that of which you have no knowledge;sur