Umm Salama bint Abu Umaya reported,
I was with the Messenger of Allah ﷺ, and Maymunah was with him, when Ibn Umm Maktum came in. This was after we had been commanded to observe the veil.The Prophet ﷺ said, "Veil yourselves from him."We said, "Messenger of Allah, is he not blind, unable to see us or recognize us?"The Prophet ﷺ replied, "Are the two of you blind as well? Can you not see him?"
Abu Dawud 4112
Hasanحدثنا محمد بن العلاء حدثنا ابن المبارك عن يونس عن الزهري قال حدثني نبهان مولى أم سلمة
عن أم سلمة قالت
كنت عند رسول الله ﷺ وعنده ميمونة فأقبل ابن أم مكتوم وذلك بعد أن أمرنا بالحجاب فقال النبي ﷺ احتجبا منه فقلنا يا رسول الله أليس أعمى لا يبصرنا ولا يعرفنا فقال النبي ﷺ أفعمياوان أنتما ألستما تبصرانه
, "And tell the believing women to lower their gaze", "And tell the believing women to lower their gaze"[Its isnad is hasan]. Tirmidhi transmitted it in the Book of Manners, the chapter on what has been said regarding women veiling themselves from men, hadith 2778, from the hadith of Abdullah bin Mubarak, with this wording, and he said, hasan sahih.Nabhan, Dhahabi rated him trustworthy in Kashif, as did Tirmidhi, Ibn Hibban, and Hakim, so his hadith does not fall below the level of hasan. See hadith 3928.