Messenger of Allah (ﷺ) delivered a Khutbah to us the like of which I had never heard from him before. He said, "If you knew what I know, you would laugh little and weep much". Thereupon those present covered their faces and began sobbing.

[Al-Bukhari and Muslim].

Another narration is: Messenger of Allah (ﷺ) heard of something about his Companions upon which he addressed them and said, "Jannah and (Hell) Fire were shown to me and I have never seen the like of this day in good and in evil. If you were to know what I know, you would laugh little and weep much". His Companions experienced such suffering on that day that had no equal. They covered their faces and began to weep.