Ibn `Umar reported Allah's Messenger (ﷺ) as saying:
The pious dreams are the seventieth part of Prophecy. (ID)
Reference (ID): Sahih Muslim 2265 a (ID)
In-book reference (ID): Book 42, Hadith 20 (ID)
USC-MSA web (English) reference(deprecated numbering scheme): Book 29, Hadith 5632 (ID)