from: Silsilah al-Ahaadeeth as-Saheehah (1993) by Shaykh al-Albaani
1) The Messenger of Allaah (sallallaahu `alaihi wa sallam) said, Make the last of
your prayer at night odd (witr).
Related by Bukhaari & Muslim.
2) Abu Salamah asked `A'ishah about the prayer of the Messenger of Allaah (sallallaahu
`alaihi wa sallam). She said, "He performed thirteen rak`ahs (in the night
prayer): he observed eight rak`ahs and would then observe Witr and then observe two
rak`ahs sitting, and when he wanted to bow, he stood up and then bowed down,
and then observed two rak`ahs in between the adhaan and iqaamah of the Dawn Prayer."
Related by Muslim.
3) Thawbaan said, "We were on a journey with the Messenger of Allaah (sallallaahu
`alaihi wa sallam), when he said, Truly, this journey is an exertion and a burden,
so when each of you has prayed Witr, he should perform two rak`ahs; if he wakes
up (then well and good), otherwise these two will be (the night prayer) for him.
Related by Daarimi (1/374), Ibn Khuzaimah in his Saheeh (2/159/1103) & Ibn Hibbaan
(683) from various routes going back to: Ibn Wahb, who said: Mu`aawiyah ibn Saalih
narrated to me from Shuraih ibn `Ubaid from `Abd ar-Rahmaan ibn Jubair ibn Nufair
from his father from Thawbaan, who said ...
Ibn Wahb has been backed up by `Abdullaah ibn Saalih, who said: Mu`aawiyah ibn Saalih
narrated to us ... etc., related by Daaraqutni (p. 177) & Tabaraani in al-Mu`jam
al-Kabeer (1410). `Abdullaah ibn Saalih is a shaykh of Bukhaari, so he can be used
as evidence in supporting others' narrations.
This hadeeth is used as evidence by Imaam Ibn Khuzaimah, "that prayer after Witr
is allowed to whoever wants to pray after it, and that the two rak`ahs which the
Prophet (sallallaahu `alaihi wa sallam) used to pray after Witr were not exclusively
for him over his Ummah, for he has ordered us to pray two rak`ahs after Witr, an
order of recommendation and preference, not one of obligation and compulsion."
Hence, it is clear to us from this hadeeth (because of his general order to his
Ummah) that the two rak`ahs after Witr were not exclusively for him; it seems that
the purpose of his command to make the last prayer at night odd was to prevent neglect
of the one odd rak`ah, so this objective is not contradicted by the two rak`ahs
after it, as established in his practice and his command. Allaah knows best.