مُسْنَدُ أَحْمَدَ
Musnad Ahmad 2067
Musnad of 'Abdullah bin al-'Abbas bin 'Abdul-Muttalib from the Prophet
It was narrated from Ibn 'Abbas that dates would be soaked for the Prophet (ﷺ) on the night before Thursday, and he would drink it on Thursday and Friday. - [The narrator] said: And I think he said: on Saturday. - Then when the time for ʼAsr came, if any of it was left over, he would give it to the servants or order that it be poured away.
Musnad Ahmad 2068Its isnad is saheeh, Muslim (2004)]