Sahih Muslim 56

Hajjāj bin ash-Shā’ir narrated to me, Ahmad bin Yūnus narrated to us, he said, I heard Zuhayr saying, Jābir said, or, I heard Jābir saying: ‘Indeed I have fifty thousand Ḥadīth that I have not narrated from at all’. [Zuhayr] said: ‘Then that day he related a Ḥadīth and said, ‘This is from the fifty thousand’.