On the day of `Arafat, some people who were with me, differed about the fasting of the Prophet (ﷺ) (p.b.u.h) some said that he was fasting while others said that he was not fasting. So I sent a bowl full of milk to him while he was riding his camel, and he drank that milk.
Sahih al-Bukhari Book 25, Hadith 142
← Previous Hadith `Abdul Malik wrote to Al-Hajjaj that he should not differ from Ibn `Umar during Hajj. On the Day of `Arafat, when the sun declined at midday, Ibn `Umar came along with me and shouted near Al- Hajjaj's cotton (cloth) tent. Al-Hajjaj came Out, wrapping himself with a waist-sheet dyed with safflower, and said, "O Abu `Abdur-Rahman! What is the matter?" He said, If you want to follow the Sunna (the tradition of the Prophet (p.b.u.h) ) then proceed (to `Arafat)." Al-Hajjaj asked, "At this very hour?" Ibn `Umar said, "Yes." He replied, "Please wait for me till I pour some water over my head (i.e. take a bath) and come out." Then Ibn `Umar dismounted and waited till Al-Hajjaj came out. So, he (Al-Hajjaj) walked in between me and my father (Ibn `Umar). I said to him, "If you want to follow the Sunna then deliver a brief sermon and hurry up for the stay at `Arafat." He started looking at `Abdullah (Ibn `Umar) (inquiringly), and when `Abdullah noticed that, he said that he had told the truth.

Sahih al-Bukhari Book 25, Hadith 141 Next Hadith → Salim said, "In the year when Al-Hajjaj bin Yusuf attacked Ibn Az-Zubair, the former asked 'Abdullah (Ibn 'Umar) what to do during the stay on the Day of 'Arafa (9th of Dhul-Hajjah). I said to him, "If you want to follow the Sunna (the legal way of the Prophet (ﷺ)) you should offer the Salat just after midday on the Day of the 'Arafa. 'Abdullah bin 'Umar said, 'He (Salim) has spoken the truth.' " They (the Companions of the Prophet (ﷺ)) used to offer the Zuhr and Asr prayer together according to the Sunna, I asked Salim, "Did Allah's Messenger (ﷺ) do that ?" Salim said, "And in doing that do you (people) follow anything else except his (ﷺ) Sunna?"

Sahih al-Bukhari Book 25, Hadith 143