…And I do not desire to be different from you in what I forbid you to do... He [Sahl] said:Every possessor of knowledge (ʿālim) who has been given knowledge of evil but does not avoid it is not a [true] possessor of knowledge. Similarly, whoever has been given knowledge of the acts of obedience but does not practise them is not a [true] possessor of knowledge.Somebody asked Sahl, ‘O Abū Muḥammad, with whom do you instruct me to sit?’ He replied, ‘With one whose limbs [i.e. bodily actions] will guide you, not his tongue.’His words, Exalted is He: