Musnad Abu Ya'la al-Mawsili 54:2

Harun ibn Ma'ruf narrated to us, Abu 'Abd al-Rahman al-Muqri' 'Abd Allah ibn Yazid narrated to us, Sa'id—meaning ibn Abi Ayyub—narrated to me, he said: 'Abd al-Rahim ibn Maymun, Abu Marhum, narrated to me, from Sahl ibn Mu'adh ibn Anas, from his father, he said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "Whoever leaves off clothing while he is able to [afford] it, out of humility for Allah, Allah will call him on the Day of Resurrection before the heads of the creation, and He will give him the choice of whichever of the garments of faith he wishes to wear."