(nb: The following excerpt is from Imām al-Nawawī’s Etiquette With the Quran.)
Explicating the Quran
It is unlawful for someone to explicate the Quran without knowledge and the qualification to speak about its meanings. The hadiths concerning this are many, and there is consensus on this. It is permissible and fitting that only scholars explicate [the Quran]; there is consensus concerning this as well. When someone is qualified to explicate the Quran—one who gathers all the tools through which [the Quran’s] meanings are known and the intended meaning is particularly apparent to him—he may indeed explicate it, if it is something attained through independent intellectual reasoning [ijtihād]. Such matters include the [Book’s] meanings and rulings—the hidden and apparent—what is universal and what is restricted, grammatical inflections, and more. But if it is something not attained through independent intellectual reasoning, but by transmitting [the thoughts of others] and explicating linguistic phrases, it is not permissible for one to communicate this except through rigorously authenticated transmissions of qualified experts. As for one who is not qualified [to offer original explications] because of not having attained the scholarly tools, it is forbidden for him to offer explication. But he may transmit explications from qualified experts.
Using Uninformed Opinion
Explicators who proffer their opinions without valid evidence may be categorized as follows: (1) One who uses a verse to justify the validity of his particular madhhab [legal approach] and to strengthen his thoughts, even though what is intended by the verse may not be preponderate in his mind as [proof of his opinion], but he nonetheless seeks only to triumph over his opponent; (2) one who intends to call to what is good, but uses a verse to justify his position without [the verse’s] indication really being apparent to him; and (3) one who explicates [the Quran’s] Arabic phrases without being familiar with their meanings as proffered by qualified scholars, while the phrases are something that can only be taken by way of qualified scholars of Arabic and explication. This includes elucidating the meaning of a phrase and its grammatical inflections, what it contains in terms of ellipses, abridgment, interpolations, literal and metaphorical meanings, universal and restricted [significance], ambiguous and detailed [aspects], matters of transposition [muqaddamahu wa mu’akhkharahu], and other things that are not so obvious.
Knowledge of Arabic Is Not Sufficient
It is not sufficient to simply know Arabic. Rather, one must also know all that qualified scholars of explication have said about [a given passage of the Quran], for they may have consensus that the apparent [meaning of a verse, for example,] is something to be disregarded and that what is intended is a specific or implied meaning, or something else contrary to the obvious. Likewise, if a phrase has different meanings and it is known that one of those meanings is intended, one then explicates each occurrence [of the phrase] that comes [separately].
All of the foregoing [depicts] the offering of explication by way of [uninformed] opinion, and this is unlawful.
And God knows best.
Arguing and Debating Without Justification
It is unlawful to argue and debate about the Quran without justification, as in the case of a person to whom it becomes apparent that there is a preponderating likelihood that a verse runs contrary to his opinion and carries a weak possibility of concurring, but still he applies it to his opinion. In fact, he [persists in] debating it even though it is apparent to him that it runs contrary to his view. (But if this not apparent to him, then he is excused.)
It is rigorously authenticated that the Messenger (God bless him and give him peace) said, “Arguing about the Quran is disbelief.” Al-Khaṭṭābī said, “What is meant by ‘arguing’ here is ‘doubt.’ Other opinions state that it is ‘debating’ in itself that is questionable or the ‘debate’ of capricious people concerning the verses that speak of destiny and the like.
Asking About the Wisdom of a Verse
Someone who wishes to ask a question—why, for example, one verse precedes another or the appropriateness of a verse in a specific context—should say, “What is the wisdom in this?”