Volume 8 · Book 76 · Hadith 429
Narrated Abu Huraira: I heard Allah's Apostle saying, "The heart of an old man remains young in two respects, i.e., his love for the world (its wealth, amusements and luxuries) and his incessant hope."
— Sahih Bukhari, Volume 8, Book 76: To make the Heart Tender (Ar-Riqaq), Hadith #429