Jarir ibn ʿAbd Allah reported: “I asked the Messenger of Allah ﷺ about an involuntary, sudden glance, and he ordered me to turn my gaze away.” 1
Furthermore, al-Qurtubi (12/230) and others relate that the verse, “and let them draw their veils over their bosoms” (24:31), was revealed because at that time women, when covering their heads with khimars (head-scarves), would let them hang down behind their backs—as the Nabataeans do—so the upper chest, neck, and ears remained exposed. Allah therefore commanded that the khimar be wrapped across the opening of the garment and pulled over the bosom.
ʿAʾisha — may Allah be pleased with her — said: “May Allah have mercy on the first female emigrants. When Allah revealed, ‘and let them draw their veils over their bosoms,’ they tore their outer garments and covered themselves with them.” In another wording: “They took their waist-wrappers, ripped them along the edges, and veiled themselves with them.” 2