مُسْنَدُ أَحْمَدَ
Musnad Ahmad 2820
Musnad of 'Abdullah bin al-'Abbas bin 'Abdul-Muttalib from the Prophet
It was narrated that Ibn ‘Abbas (رضي الله عنه) said: The Messenger of Allah (ﷺ) said: “Whoever learns anything about astrology has learned a branch of magic, and whoever learns more of it learns more of that.”
Musnad Ahmad 2840Its isnad is saheeh]