Wedlock, Marriage (Nikaah)
Bukhari :: Book 7 :: Volume 62 :: Hadith 137
Narrated Abu Said Al-Khudri:
We got female captives in the war booty and we used to do coitus interruptus with them. So we asked Allah's Apostle about it and he said, "Do you really do that?" repeating the question thrice, "There is no soul that is destined to exist but will come into existence, till the Day of Resurrection."