From Sahih Bukhari (Hadith 6638):
Narrated Abu Dhar:I reached him (the Prophet (ﷺ) ) while in the shade of the Ka`ba; he was saying, "They are the losers, by the Lord of the Ka`ba! They are the losers, by the Lord of the Ka`ba!" I said (to myself ), "What is wrong with me? Is anything improper detected in me? What is wrong with me? Then I sat beside him and he kept on saying his statement. I could not remain quiet, and Allah knows in what sorrowful state I was at that time. So I said, ' Who are they (the losers)? Let My father and mother be sacrificed for you, O Allah's Messenger (ﷺ)!" He said, "They are the wealthy people, except the one who does like this and like this and like this (i.e., spends of his wealth in Allah's Cause)
Reference: Bukhari 6638