Narrated Abu 'Uthman An-Nahdi:
from Ibn Mas'ud who said: The Messenger of Allah (ﷺ) performed 'Isha, then he turned and took the hand of 'Abdullah bin Mas'ud until he went with him to the wide valley of Makkah. He sat him down, then he drew a line around him. Then he said: 'Do not go beyond your line, for indeed there shall come some men to you, but do not speak to them for they shall not speak to you.' He said: Then the Messenger of Allah (ﷺ) went to where he wanted to go, and while I was sitting within the line, some men came to me that appeared as if they were from Az-Zut (A dark people, either from North Africa or India. See Tuhfat Al-Ahwadhi and An-Nihayah), both their hair and their bodies. I did not see nakedness nor covering. They ended up before me but they did not pass the line. Then they returned toward the Messenger of Allah (ﷺ) and when it was near the end of the night, the Messenger of Allah (ﷺ) came to me while I was sitting, and he said: I have been awake watching all night' then he entered into the line with me and lay down on my thigh to sleep. And the Messenger of Allah (ﷺ) would snore when he slept. So while I was sitting there, and the Messenger of Allah (ﷺ) was sleeping (with his head resting) on my thigh, there appeared some men wearing white garments, and Allah knows best just how handsome they were. They came towards me, and a group of them sat at the head of the Messenger of Allah (ﷺ), and a group at his feet. Then they said to each other: 'We have not ever seen a slave (of Allah) who was given the likes of what this Prophet has been given. Indeed his eyes sleep but his heart remains awake. His parable is that of a chief who built a castle, then he placed a table-spread in it, and invited the people to eat from his food and drink. So whoever answers his invitation, he eats from his food and drinks from his drink. Whoever does not answer, he is punished - or he said - he is chastised.' Then they alighted and the Messenger of Allah (ﷺ) awoke at that time, and said: 'I heard what they were saying. Do you know who they were?' I said: 'Allah and His Messenger know better.' He said: 'They were the angels. Do you know the meaning of the parable they stated?' I said: 'Allah and His Messenger know better.' He said: 'The meaning is that Ar-Rahman [Most Blessed and Most High] built Paradise, and He invited His Slaves to it. Whoever replies he shall enter Paradise, and whoever does not reply, he shall be punished or chastised.'