Sahih Bukhari Volume 2, Book 25, Hadith 1666

حَدَّثَنَا فَرْوَةُ بْنُ أَبِي الْمَغْرَاءِ، حَدَّثَنَا عَلِيُّ بْنُ مُسْهِرٍ، عَنْ هِشَامِ بْنِ عُرْوَةَ، قَالَ عُرْوَةُ كَانَ النَّاسُ يَطُوفُونَ فِي الْجَاهِلِيَّةِ عُرَاةً إِلاَّ الْحُمْسَ، وَالْحُمْسُ قُرَيْشٌ وَمَا وَلَدَتْ، وَكَانَتِ الْحُمْسُ يَحْتَسِبُونَ عَلَى النَّاسِ يُعْطِي الرَّجُلُ الرَّجُلَ الثِّيَابَ يَطُوفُ فِيهَا، وَتُعْطِي الْمَرْأَةُ الْمَرْأَةَ الثِّيَابَ تَطُوفُ فِيهَا، فَمَنْ لَمْ يُعْطِهِ الْحُمْسُ طَافَ بِالْبَيْتِ عُرْيَانًا، وَكَانَ يُفِيضُ جَمَاعَةُ النَّاسِ مِنْ عَرَفَاتٍ، وَيُفِيضُ الْحُمْسُ مِنْ جَمْعٍ‏.‏ قَالَ وَأَخْبَرَنِي أَبِي عَنْ عَائِشَةَ ـ رضى الله عنها ـ أَنَّ هَذِهِ الآيَةَ نَزَلَتْ فِي الْحُمْسِ ‏{‏ثُمَّ أَفِيضُوا مِنْ حَيْثُ أَفَاضَ النَّاسُ‏}‏ قَالَ كَانُوا يُفِيضُونَ مِنْ جَمْعٍ فَدُفِعُوا إِلَى عَرَفَاتٍ‏

Narrated By 'Urwa : During the pre-Islamic period of Ignorance, the people used to perform Tawaf of the Ka'ba naked except the Hums; and the Hums were Quraish and their offspring. The Hums used to give clothes to the men who would perform the Tawaf wearing them; and women (of the Hums) used to give clothes to the women who would perform the Tawaf wearing them. Those to whom the Hums did not give clothes would perform Tawaf round the Ka'ba naked. Most of the people used to go away (disperse) directly from 'Arafat but they (Hums) used to depart after staying at Al-Muzdalifa. 'Urwa added, "My father narrated that 'Aisha had said, 'The following verses were revealed about the Hums: Then depart from the place whence all the people depart... (2.199) 'Urwa added, "They (the Hums) used to stay at Al-Muzdalifa and used to depart from there (to Mina) and so they were sent to 'Arafat (by Allah's order)."