It wasnarrated that Bara' bin 'Azib said:
"We were talking abouthow,on the Day of Badr, the Companions of the Messenger of Allah(ﷺ)numbered three hundred ten and something, the same number as theCompanions of (Talut) who crossed the river with him, and no onecrossed the river with him but a believer."
English reference: Vol. 4, Book 24, Hadith 2828
Arabic reference: Book 24, Hadith 2935