Ibn 'Abbas narrated that the Prophet (s.a.w) said:
"Whoever lies about having a dream, he will be required to knot two barely kernels together on the Day Of Judgment., and he will never be able to knot them together." (ES)
English reference (ES): Vol. 4, Book 8, Hadith 2283 (ES)
Arabic reference (ES): Book 34, Hadith 2452 (ES)