مُسْنَدُ أَحْمَدَ
Musnad Ahmad 2258
Musnad of 'Abdullah bin al-'Abbas bin 'Abdul-Muttalib from the Prophet
It was narrated from Ibn 'Abbas (رضي الله عنه) that Usamah bin Zaid was riding behind the Messenger of Allah (ﷺ) on the day of 'Arafah. He went into a mountain pass and passed water, then he did wudoo’, and got back on his mount, but he did not pray.
Musnad Ahmad 2265Saheeh]