He heard him speaking about Badr and those who went out to Badr.
في قوله تعالى: {لا يستوي القعدون من المؤمنين} [النساء: ٩٥]
أنه سمعه يقول: عن بدر، والخارجون إلى بدر.
No references are available.
Bukhari narrated it in the Book of Military Expeditions (3954), from Ibrahim bin Musa, who said, Hisham (that is, Ibn Yusuf al-Sanani) informed us, that Ibn Jurayj informed them, saying, Abdul-Kareem (that is, al-Jazari) informed me, from Miqsam (that is, Abu Qasim), from Ibn Abbas, and he mentioned it. Miqsam was the freed slave of Abdullah bin Harith, and it is also said he was the freed slave of Ibn Abbas, due to how closely he stayed attached to him.