Abu Dawud
Purification (Kitab Al-Taharah)
Book Number: 001 / Hadith Number: 337
Narated By Abdullah ibn Abbas : A man was injured during the lifetime of the Apostle of Allah (pbuh); he then had a sexual dream, and he was advised to wash and he washed himself. Consequently he died. When this was reported to the Apostle of Allah (pbuh) he said: They killed him; may Allah kill them! Is not inquiry the cure of ignorance?