So he did veil her. Later, when¹ Allah commanded that they should be addressed only from behind a curtain, and when He instructed His wives, His daughters, and the believing women to draw their jilbāb (outer cloaks) over themselves—
The jilbāb is a large mantle; Ibn Masʿūd and others refer to it as a ridāʾ (cloak), while ordinary people call it an izār (wrap). It is an ample garment that covers a woman’s head and her entire body.
ʿUbayda and others have reported that she is to lower it from above her head so that nothing is visible except one eye; of the same kind is the niqāb (face veil), and women used to wear the niqāb.
It is authentically narrated that “a woman in iḥrām is not to wear the niqāb nor gloves.”
If, then, they were commanded to don the jilbāb so that they would not be recognized—and that is itself a covering of the face—
“al-Hijab,” p. 50. This differs from the female slaves of the Prophet (peace and blessings be upon him), since the hadith indicates that he did not require them to veil their faces. As for claiming that the hadith indicates that the sunnah for slave women is, at the very least, not to cover their heads and necks with a jilbab or khimar, this is incorrect, as I explained in the work cited above, pp. 44–45. The hadith is reported by both al-Bukhari and Muslim; its documentation can be found there, p. 46.
(1) This is how it appears in the text; perhaps the correct reading is “therefore.”
(2) The verse states: “That is more likely that they will be recognized.” Taking the word “not” as implied here goes against the basic rule and has no justification, since the meaning is perfectly sound without it. Ibn Kathir states in his commentary on this verse: “That is, when they do so, they will be recognized as free women, not slave women or prostitutes.” A similar explanation appears in Tafsir Ibn Jarir. Accordingly, the statement “and this means covering the face” has no basis, and the same applies to what follows. Indeed, a hadith in an authentic collection indicates that wearing the niqab was known, but it does not prove that it was obligatory or that it is what the verse intended.