Sahih Bukhari

Narrated `Abdullah bin `Umar:I heard Allah's Messenger (ﷺ) saying, ""While I was sleeping, I saw a bowl full of milk was brought to me and I drank of it (to my fill) till I noticed its wetness flowing (in my body). Then I gave the remaining of it to `Umar."" They asked, ""O Allah's Messenger (ﷺ)! What have you interpreted (about the dream)? He said, ""(It is Religious) knowledge."" (See Hadith No)