According to the vast majority of rational thinkers, a definition stands in the same position as a name: it simply spells out in detail what the name conveys in a general way. The purpose of a definition is to distinguish the thing defined from everything else, and this is achieved by a property that inseparably accompanies it—both in what it includes and what it excludes—so that the definition is at once comprehensive and exclusive.
Still, no one has the right to advance a claim that is not self-evident unless he brings proof. Thus, when a person seeks to define the referent of a term—saying, for example, that wine is “that which intoxicates,” or that backbiting is “mentioning your brother with what he dislikes,” or that arrogance is “rejecting the truth and belittling people”—he must show that his wording really matches what the term denotes. He may do this by citing transmission from the Lawgiver who employed these words. For instance, it is soundly reported that the Prophet (may Allah bless him and grant him peace) said:
“Every intoxicant is wine.”
By unanimous agreement, whatever does not intoxicate is not wine; hence wine is the intoxicant. Likewise, it is authentically reported that the Prophet (may Allah bless him and grant him peace) was asked, “Messenger of Allah, what is backbiting?” He replied:
“Mentioning your brother with what he dislikes.”
The questioner then said, “What if my brother actually possesses what I say about him?” He answered:
“If what you say about him is true, you have backbitten him; and if it is not true, you have slandered him.”
Now, suppose someone objects by citing another rigorously authenticated report: when Fāṭimah bint Qays consulted the Prophet about the men who had proposed to her, she said, “Abū Jahm and Muʿāwiyah have asked for my hand.” He replied:
“As for Abū Jahm, he is a man who beats women”—and in another wording, “he never lays his stick down from his shoulder—“and as for Muʿāwiyah, he is penniless; marry Usāmah.”
If the objector says, “He spoke of each man with something he would dislike, and backbiting is forbidden,” the answer, based on either of two premises, is as follows: (1) we may deny that this falls under the definition of backbiting; or (2) if we concede that it does, the report shows that backbiting is permissible when an overriding benefit exists, such as advising someone who seeks counsel. Because she sought his advice, it was obligatory for him to counsel her. The same principle applies to criticizing unreliable ḥadīth transmitters, exposing a lying witness, voicing the complaint of an oppressed person, and similar situations