مُسْنَدُ أَحْمَدَ
Musnad Ahmad 3160
Musnad of 'Abdullah bin al-'Abbas bin 'Abdul-Muttalib from the Prophet
It was narrated that Ibn ‘Abbas (رضي الله عنه) said: I came when the Messenger of Allah (ﷺ) was praying in Mina and I was riding a donkey, I let it go in front of the row and joined the prayer, and I had reached the age of puberty, but he did not rebuke me for that.
Musnad Ahmad 3184lts isnad is saheeh, al-Bukhari (76) and Muslim (504)]