On the authority of Abu Hurayrah, from the Prophet, peace and blessings be upon him, regarding it: "and letting the beard grow." And on the authority of Ibrahim al-Nakha'i similarly, and he mentioned letting the beard grow and circumcision.

29 - Chapter: The Siwak for the One Who Rises at Night

55 - Muhammad ibn Kathir narrated to us, Sufyan informed us, on the authority of Mansur and Husayn, on the authority of Abu Wa'il, on the authority of Hudhayfah: that when the Messenger of Allah, peace and blessings be upon him, rose at night, he would rub his mouth with the siwak.

56 - Musa ibn Isma'il narrated to us, Hammad narrated to us, Bahz ibn Hakim informed us, on the authority of Zurarah ibn Awfa, on the authority of Sa'd ibn Hisham, on the authority of 'A'ishah: that the Prophet, peace and blessings be upon him, would have his water for ablution and his siwak placed for him, and when he rose at night, he would relieve himself and then use the siwak.

(1) Its chain of transmission is authentic. Sufyan: he is al-Thawri, and Mansur: he is ibn al-Mu'tamir, and Husayn: he is ibn 'Abd al-Rahman al-Sulami, and Abu Wa'il: he is Shaqiq ibn Salamah.
Al-Bukhari also narrated it (245), (889), and (1136), Muslim (255), al-Nasa'i in "al-Kubra" (2), and Ibn Majah (286) through various routes from Abu Wa'il, with this chain of transmission.
It is in "Musnad Ahmad" (23242), and "Sahih Ibn Hibban" (1072).
His saying: "he would rub his mouth with the siwak." The author of "al-Nihayah" said: meaning he would rub his teeth and clean them, and it was said: it is to use the siwak from lower to upper, and the origin of al-shaws is washing.

(2) Its chain of transmission is authentic. Hammad: he is ibn Salamah.
It was also narrated within a lengthy hadith by al-Nasa'i in "al-Kubra" (448) and (1239), and Ibn Majah (1191) via the route of Qatadah, from Zurarah ibn Awfa, with this chain of transmission.
It is in "Musnad Ahmad" (24269).
His saying: "he would relieve himself" (takhalla), from al-khala': the place where no one is, and it is used for the place prepared for relieving oneself, and for the act of relieving oneself itself, naming the state by the name of the place, and that is what is meant here.