مُسْنَدُ أَحْمَدَ
Musnad Ahmad 3308
Musnad of 'Abdullah bin al-'Abbas bin 'Abdul-Muttalib from the Prophet
It was narrated from Hisham bin Ishaq bin 'Abdullah bin Kinanah that his father said: One of the governors sent me to Ibn ‘Abbas (رضي الله عنه) to ask him about prayers for rain. Ibn ‘Abbas (رضي الله عنه) said: What prevented him from asking me? The Messenger of Allah (ﷺ) went out humbly and wearing shabby clothes, walking with a lowly and moderate gait, beseeching, and he prayed two rak'ahs as is done on Eid, but he did not deliver a speech as you do.
Musnad Ahmad 3331Its isnad is hasun]