A Sober Second Thought: When and How Should Changes in Islamic Law be Made?

Change and adaptability in Islamic law are subjects that stir the hearts of many Muslims today, particularly as the pace of transformation in human society has accelerated beyond anything witnessed in previous generations. Some call for change out of a desire to abandon the inherited legal tradition altogether, while others call for it out of a sincere wish to see the Sharīʿah furnish answers to the economic, technological, and demographic realities of the age. The central concern is how much Islamic law is meant to change with changing circumstances, and, just as importantly, how much its wisdom ought to lead Muslims to resist those changes. The aim here is not to settle every particular question but to establish sound parameters, a disciplined framework within which such conversations may take place, so that young Muslims do not, out of sincere but hasty emotion, cast aside the accumulated wisdom of the tradition in favour of an untested reliance upon the present.

It is important first to define "Islamic law." Though often used as a synonym for Sharīʿah, this usage risks giving the impression that the law is a ready-made code lifted directly from the Qurʾān and Sunnah. In truth, many substantive rulings are the product of juristic reasoning, the enterprise known as fiqh. Islamic law, then, refers to the whole body of substantive rulings existing along a spectrum: from those that are self-evident and require no reasoning, such as the obligation of the five daily prayers, to those demanding rigorous ijtihād.

A defining and distinguishing feature of Islamic law is its fidelity to divine revelation. The believer is bound to seek God's ruling, for Allah says, "It is not for a believing man or a believing woman, when Allah and His Messenger have decided a matter, that they should have any choice about their affair" (Qurʾān 33:36). He also says, "But no, by your Lord, they will not truly believe until they make you judge concerning that over which they dispute among themselves" (Qurʾān 4:65), and He commands, "O you who have believed, obey Allah and obey the Messenger and those in authority among you" (Qurʾān 4:59). God's law is discoverable through the Qurʾān and the Sunnah, joined by the agreed-upon extra-textual sources that themselves derive legitimacy from revelation, namely consensus (ijmāʿ) and analogical reasoning (qiyās). The task of the jurist is to discover what the sources dictate, not to arrive at a predetermined outcome pleasing to his own sensibility. Human beings possess a sense of justice, and the Sharīʿah grants it a role, yet this sense is a tool empowered by revelation and does not rule over it. To empower one's own limited views at the expense of God's law is to follow hawā, mere desire, which the Qurʾān condemns: "So follow it and do not follow the desires of those who do not know" (Qurʾān 45:18), and, "So judge between them by what Allah has revealed and do not follow their desires away from what has come to you of the truth" (Qurʾān 5:48).

A common objection holds that Islamic law is nothing more than the subjective, culturally-conditioned opinions of long-dead scholars, such that we are not bound by their rulings and are free to fashion a modern makeover. This claim must be answered. Firstly, not everything is open to subjective reading. No rational person can read the Qurʾān and claim it permits murder. Certain matters are definitive (qaṭʿī), whether derived directly from the text or established by an unbroken fourteen-century consensus, such as the prohibitions of usury, swine, and fornication, and the obligations of prayer and fasting. Secondly, while a degree of subjectivity is unavoidable in interpreting any text, and this indeed explains the existence of differing schools that agree on much and differ on some particulars, such as whether a starving person may eat only enough to survive or eat his fill, this does not render the enterprise arbitrary. The qualified jurist must root his conclusion in scripture; an opinion detached from revelation carries no weight. The very supremacy granted to the sources minimises the intrusion of personal bias. Indeed, the paucity of legal opinions, and the existence of only four principal Sunni schools (or six if the Shīʿah and Ibāḍiyyah are included), testifies that the tradition is far more disciplined than arbitrary opinion would produce. In this light, the work of the classical jurists enjoys a level of objectivity superior to that of those who call for change on the basis of nothing more than modern sensibility. This does not deny that time-specific factors shaped some rulings; where they did, a change in those factors may change the ruling, but one must carefully distinguish which rulings rest on such factors and which do not.

Yet the supremacy of the sources does not render the law rigid. There exist avenues for adaptation that are themselves sanctioned by revelation, so that such change is an application of God's law rather than a departure from it. The first is the analysis of the ʿillah, the ratio legis. When the ʿillah is present the ruling applies, and when it is absent the ruling lapses, though the ruling itself is never suspended, for that would amount to abrogating God's command. Thus intoxication is the ʿillah for the prohibition of wine, extended by qiyās to narcotics. The Companions understood this: the Prophet ﷺ commanded that a stray camel be left alone because it could survive until its owner found it, yet ʿUthmān ibn ʿAffān later ordered such camels seized and sold when people grew willing to falsely claim lost property, for the ʿillah had changed. The 20th-century scholar Shaykh Muṣṭafā al-Zarqāʾ noted two roles of custom in this analysis: custom serving as the ʿillah itself, and a new custom vitiating an existing ʿillah. He cited Abū Yūsuf (d. 798), student of Abū Ḥanīfah, on ribā, holding that whether wheat is traded by weight or volume depends on prevailing commercial custom. Likewise, the silence of a virgin as consent to marriage rested on the custom of bashfulness, so that where such custom no longer prevails, verbal consent becomes required. And uncertainty (gharar) over an unspecified currency may be removed when custom fixes the currency of a market.

Several clarifications guard this analysis. The ʿillah must be apparent (ẓāhir) and measurable (munḍabiṭ), unlike the ḥikmah, the abstract wisdom behind a ruling. We prohibit a substance because it intoxicates, not because we individually assess whether its wisdom is served. Relying on the ḥikmah invites chaos: one might claim, falsely, that the prohibition of zinā aimed only at securing lineage and is now dispensable through modern technology. Anchoring the ruling to a concrete ʿillah, the absence of a valid marital contract, forecloses such tampering. Yet jurists are not mechanical; the presumptive ʿillah of consent, indicated by a contract, may be rebutted by clear evidence of duress (ikrāh).

Custom (ʿurf) also gives substance to generally-worded rulings. The requirement that a court witness be of upright character (ʿadl) is fixed, yet what constitutes uprightness varies; al-Shāṭibī (d. 1388) observed that uncovering the head is impugning in the eastern lands but not in the Maghrib, and the ruling differs accordingly. Hence the maxims "custom is determinative" (al-ʿādah muḥakkamah) and "there is no objection to the changing of rulings with changing times." Custom shapes the quantum of spousal maintenance, the implied terms of a lease, and serves as prima facie evidence in judicial disputes. Al-Sarakhsī (d. 1090) stated, "That which is established by custom is like that which is established by text," meaning not that custom equals revelation, but that where revelation has empowered custom, reliance upon it is reliance upon the text.

Custom must be kept in its place. It may serve as an ʿillah only where evidence points to it, lest every ruling be dismissed as a relic of Arab usage. It gives effect to a general rule but cannot carve out an exception to one; if an action is prohibited, its later prevalence does not exempt it. Nor can custom override a specific injunction, such as the fixed waiting period (ʿiddah) defined in the Qurʾān. Al-Shāṭibī affirmed that variation by custom is not variation in the divine command itself. Ibn al-Qayyim devoted a chapter to the changing of fatwā with changing times and customs, and al-Qarāfī (d. 1285) held that to persist in a custom-based ruling after its custom has vanished is "contrary to consensus" and "ignorance in religion," adding that even a non-mujtahid may apply such change. Ibn ʿĀbidīn likewise noted that many rulings of a mujtahid rested on the custom of his time.

Further avenues lie in maṣlaḥah, the securing of benefit and repelling of harm, oriented toward the five necessities: religion, life, intellect, progeny, and property. By agreement of all schools, necessity (ḍarūrah) renders the forbidden permissible (al-ḍarūrāt tubīḥ al-maḥẓūrāt), as in eating carrion to escape death, or, in al-Ghazālī's example, firing upon an enemy using Muslim captives as shields to repel a greater, universal harm. More contested are the Ḥanafī tool of istiḥsān and the Mālikī istiṣlāḥ, which employ a lower threshold of hardship to carve out exceptions, as with the strict liability of the public tradesman, or to legislate where no text exists, as with the Companions' compilation of the Qurʾān into one volume. Yet these are bounded: al-Shāṭibī required that a valid maṣlaḥah mursalah be suitable to the objectives, rational rather than ritual, and answer a necessity or genuine hardship. A maṣlaḥah that violates a definitive text is invalidated (mulghāh), as in the false fatwā forbidding a wealthy king from freeing a slave in expiation. These are legal instruments, not ideological ones, and cannot be wielded to discard rulings merely because they clash with a prevailing "ism."

In sum, we are those who submit. We do not decide beforehand that change is needed and then reason toward it; we approach the Book and the Sunnah faithfully and discover the ruling and its scope. A definitive ruling ceases to apply only where its ʿillah is absent or where necessity compels, never through dubious speculation about the Prophet's cultural context, for such a door would displace the Sharīʿah entirely, as in the absurd claim that ḥijāb was merely for nocturnal privacy now rendered obsolete by plumbing. Rulings that are not definitive and rest on time-specific factors may change through proper avenues and qualified scholars; those resting purely on textual evidence change only when stronger textual evidence is produced, a change of proof (ikhtilāf dalīl wa burhān) rather than of era (ikhtilāf waqt wa zamān). What emerges is a balance between saving the law from arbitrariness and allowing it to respond justly to changed circumstances, a balance the tradition has maintained not despite its fidelity to the Qurʾān and Sunnah, but because of it. Change is indeed needed, yet the change some envision differs from the change the Sharīʿah permits.