Another group maintained that the feet may be purified by either method—washing or wiping—and that the choice is left to the individual performing the ablution.
The root of their disagreement is the two well-known variant readings of the verse of ablution (Qur’an 5:6). One reading vocalizes the phrase “and your feet” in the accusative—wa arjulakum—linking it to the limbs that are washed; the other vocalizes it in the genitive—wa arjulikum—linking it to those that are wiped. The accusative reading clearly implies washing, just as the genitive unequivocally implies wiping. Whoever held that only one of the two acts is obligatorily intended—either washing or wiping—accordingly preferred the outward sense of one reading over the other and, by interpretation, redirected the second reading to the meaning conveyed by the first.
By contrast, whoever judged that the outward import of both readings is equally strong, with neither one furnishing clearer evidence than the other, treated the matter as a divinely mandated choice (wājib mukhayyar), akin to the alternative forms of expiation for broken oaths. This was the view of al-Ṭabarī and Dāwūd.
The majority offered several explanations for the genitive reading; the soundest is that the coordination is based on the wording rather than the meaning—an accepted feature of Arabic speech, as in the poet’s verse:
“Time has played with her and altered her
after me, the pure south winds and the rain,”
where “the rain” remains in the genitive; had the poet coordinated according to meaning he would have put it in the nominative.
The second party—those who made wiping obligatory—explained the accusative reading as coordination with the syntactic position, as in the poet’s line:
“We are neither mountains nor iron.”
The majority, however, reinforced their own position by what is authentically reported from the Prophet (peace and blessings be upon him). Seeing people who had not fully washed their feet during ablution, he said, “Woe to the heels from the Fire.” They argued that this indicates washing is obligatory, for punishment is attached only to the neglect of an obligatory act.
Yet this is not definitive proof, for the warning concerns their leaving the heels untouched by water. Clearly, once a person begins washing, he must wash the entire foot, just as one who begins wiping must wipe the whole foot, according to those who allow a choice between the two methods.
This is further supported by another report narrated by Muslim: “We began to wipe over our feet, whereupon he called out, ‘Woe to the heels from the Fire!’” Although this ḥadīth is commonly cited to prohibit wiping, it actually favors its permissibility, for the threat is attached to failing to cover the whole area, not to the type of purification; the report is silent on that point, which implies both methods are acceptable.
The permissibility of wiping is also related—by way of reasoned inference—from certain Companions and Successors. Still, washing is more fitting for the feet than wiping, just as wiping is more fitting for the head than—