Sahih al-Bukhari Book 33, Hadith 10
Safiya, the wife of the Prophet (ﷺ) told me that she went to Allah's Messenger (ﷺ) to visit him in the mosque
while he was in I`tikaf in the last ten days of Ramadan. She had a talk with him for a while, then she
got up in order to return home. The Prophet (ﷺ) accompanied her. When they reached the gate of the
mosque, opposite the door of Um-Salama, two Ansari men were passing by and they greeted Allah's
Apostle . He told them: Do not run away! And said, "She is (my wife) Safiya bint Huyai." Both of
them said, "Subhan Allah, (How dare we think of any evil) O Allah's Messenger (ﷺ)!" And they felt it. The
Prophet said (to them), "Satan reaches everywhere in the human body as blood reaches in it,
(everywhere in one's body). I was afraid lest Satan might insert an evil thought in your minds."
The Prophet (ﷺ) intended to practice I`tikaf and when he reached the place where he intended to perform I`tikaf, he saw some tents, the tents of `Aisha, Hafsa and Zainab. So, he said, "Do you consider that they intended to do righteousness by doing this?" And then he went away and did not perform I`tikaf (in Ramadan) but performed it in the month of Shawwal for ten days.
I asked Abu Sa`id Al-Khudri, "Did you hear Allah's Messenger (ﷺ) talking about the Night of Qadr?" He replied in the affirmative and said, "Once we were in I`tikaf with Allah's Messenger (ﷺ) in the middle ten days of (Ramadan) and we came out of it in the morning of the twentieth, and Allah's Messenger (ﷺ)delivered a sermon on the 20th (of Ramadan) and said, 'I was informed (of the date) of the Night of Qadr (in my dream) but had forgotten it. So, look for it in the odd nights of the last ten nights of the month of Ramadan. I saw myself prostrating in mud and water on that night (as a sign of the Night of Qadr). So, whoever had been in I`tikaf with Allah's Messenger (ﷺ) should return for it.' The people returned to the mosque (for I`tikaf). There was no trace of clouds in the sky. But all of a sudden a cloud came and it rained. Then the prayer was established (they stood for the prayer) and Allah's Messenger (ﷺ) prostrated in mud and water and I saw mud over the forehead and the nose of the Prophet.