Abu Huraira reported that Allah's Apostle (ﷺ) said:
Allah, the Exalted and Glorious, said: I have prepared for My pious servants which no eye (has ever) seen, no ear has (ever) heard and no human heart has ever perceived those bounties leaving apart (those bounties) about which Allah has informed you.
Reference: Sahih Muslim 2824 b
In-book reference: Book 53, Hadith 4
USC-MSA web (English) reference(deprecated numbering scheme): Book 40, Hadith 6781