That he heard the Prophet ﷺ on the pulpit reciting:-- "They will cry: "O Malik!' (43.77) (Malik is the gate-keeper (angel) of the (Hell) Fire.)  

أَنَّهُ سَمِعَ النَّبِيَّ ﷺ يَقْرَأُ عَلَى الْمِنْبَرِ {وَنَادَوْا يَا مَالِكُ }