Musnad Ahmad 30:2097

Ali ibn Ishaq narrated to us, he said: Abdullah informed us, Zubayr ibn Sa’id informed us - then he mentioned a hadith from Safwan ibn Sulaym - he said: And Safwan ibn Sulaym also narrated from ‘Ata’ ibn Yasar, from Abu Hurayrah, from the Messenger of Allah (peace and blessings of Allah be upon him), who said: "Indeed, a man speaks a word to make his companions laugh, by which he falls further than the Pleiades."