It was narrated from Makhramah bin Sulaiman that Kuraib – the freed slave of Ibn ‘Abbas – told him:
“I asked Ibn ‘Abbas: ‘How did the Messenger of Allah (pbuh) pray at night?’ He said:
‘He prayed eleven Rak’ahs including Witr, then he slept deeply until I could hear him snoring, then Bilal came to him and said: “The prayer, O Messenger of Allah!” Then he got up and prayed two brief Rak’ahs then led the people in prayer, *and he did not perform Wudu’.’*
Source
Grade: Sahih (Darussalam)
Sunan an-Nasa’i, The Book of the Adhan (The Call to Prayer)
English reference
Vol. 1, Book 7, Hadith 687 Arabic reference
Book 7, Hadith 694
https://islamqa.info/en/43355
Rasoolullah sallallahu alaihi wasallam’s Heart does not sleep
Narrated ‘Abu Salma bin `Abdur Rahman:
I asked `Aisha, “How is the prayer of Allah’s Messenger (pbuh) during the month of Ramadan.” She said,
“Allah’s Messenger (pbuh) never exceeded eleven rak`at in Ramadan or in other months; he used to offer four rak`at– do not ask me about their beauty and length, then four rak`at, do not ask me about their beauty and length, and then three rak`at.”
Aisha further said, “I said, ‘O Allah’s Messenger (pbuh)! Do you sleep before offering the witr prayer?’ He replied,
‘O `Aisha! My eyes sleep but my heart remains awake’!”
Source
Sahih al-Bukhari, Prayer at Night (Tahajjud)
Book 19, Hadith 28