عَنْ جَابِرٍ قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «إِذَا خَطَبَ أَحَدُكُمُ الْمَرْأَةَ فَإِنِ اسْتَطَاعَ أَنْ يَنْظُرَ إِلَى مَا يَدْعُوهُ إِلَى نِكَاحهَا فَلْيفْعَل» . رَوَاهُ أَبُو دَاوُد

Umm Salama said

I was with God’s Messenger along with Maimuna when Ibn Umm Maktum approached and came in to visit him, so he told us to veil ourselves. I said, "Messenger of God, is he not blind and unable to see us?” He replied, "Are you blind and unable to see him?” Ahmad, Tirmidhi and Abu Dawud transmitted it.