“We were talking about how, on the Day of Badr, the Companions of the Messenger of Allah ﷺ numbered three hundred ten and something, the same number as the Companions of (Talut) who crossed the river with him, and no one crossed the river with him but a believer.” (Using translation from Ibn Mājah 2828)
أَنَّ عِدَّةَ أَصْحَابِ رَسُولِ اللهِ ﷺ كَانُوا يَوْمَ بَدْرٍ عَلَى عِدَّةِ أَصْحَابِ طَالُوتَ يَوْمَ جَالُوتَ ثَلَاثَ مِائَةٍ وَبِضْعَةَ عَشَرَ الَّذِينَ جَازُوا مَعَهُ النَّهْرَ قَالَ وَلَمْ يُجَاوِزْ مَعَهُ النَّهْرَ إِلَّا مُؤْمِنٌ