who was one of those who witnessed (the Pledge of allegiance beneath) the Tree: Allah's Messenger (ﷺ) and his companions were given Sawiq and they chewed it.
Sahih al-Bukhari Book 64, Hadith 217
← Previous Hadith The same narration was told by Majzaa from a man called Uhban bin Aus who was one of those who had witnessed (the Pledge of allegiance beneath) the Tree., and who had some trouble in his knee so that while doing prostrations, he used to put a pillow underneath his knee.

Sahih al-Bukhari Book 64, Hadith 216 Next Hadith → I asked Aidh bin `Amr, who was one of the companions of the Prophet (ﷺ) one of those (who gave the allegiance to the Prophet (ﷺ) the Tree: "Can the witr prayer be repeated (in one night)?" He said, "If you have offered it in the first part of the night, you should not repeat it in the last part 'of the night." (See Fath-ul-Bari page 458 Vol 8th).

Sahih al-Bukhari Book 64, Hadith 218