The question/claim: "Is the headscarf explicitly obligatory in the Qur'an? On one reading, 24:31 only requires covering the bosom; covering the head is an Arab custom, not a Qur'anic command."
What does the Qur'an say? — 24:31 and 33:59
Two verses are directly relevant:
"…let them draw their head-coverings (khumur) over their necklines/bosoms…" (24:31)
"…let them draw their outer garments (jalābīb) over themselves (when they go out); that is more fitting that they be recognised and not harmed." (33:59)
The key word: "khumur" (head-coverings)
The word in 24:31 is "khumur" (sing. khimār, خِمار), from the root kh-m-r = to cover, conceal. In classical Arabic and the lexicons (Lane's Lexicon) the khimār is a woman's head-covering — indeed wine is called khamr from the same root because it "covers" the mind. So the verse commands drawing a covering that already covers the head down over the bosom/neckline.
Two readings follow:
- Majority reading: the verse presumes the khimār is a head-covering and commands extending it over the bosom; head-covering is thus taken for granted → covering is a Qur'anic command.
- Alternative reading: the verse's explicit command is to cover the bosom/neckline; the word "head" does not occur in it. On this reading the aim is modesty and covering the chest; the khimār being a head-cloth is the dress of that time, and the universal command is the principle of modesty, not the "head" as such.
An honest limit
- Certain at the level of the text: the Qur'an commands modesty/covering for women (and, in 33:59, outdoors); drawing the khimār over the bosom is an explicit command. So "the Qur'an says nothing about covering" is false.
- Contested at the level of interpretation: whether the head itself is a separate obligation. "Khimār" is linguistically a head-cover (which strengthens the majority); yet what the verse literally commands is covering the bosom (which leaves the door open to the alternative).
- The scope of "illā mā ẓahara minhā" (except what is apparent — face/hands, etc.) is likewise a matter of interpretation.
Conclusion: the principle of modesty and covering the bosom is the Qur'an's explicit command; that "covering the head" is a standalone obligation is linguistically strong but is established by interpretation, not by the literal wording. We do not close this one-sidedly; we give both readings with their source.
Source: Qur'anic verses (M. Okuyan meal) + classical lexicon (root of khimār). Presented with a text/interpretation distinction; not a fiqh fatwa.