Onan in Wikipedia

In the Biblical Book of Genesis, Onan (Hebrew: אוֹנָן, Modern Onan Tiberian ʼÔnān ; "Strong") was the second son of Judah.[1] Certain interpretations of the narrative concerning him have led to the term onanism, which means coitus interruptus. According to the text, after God had killed Onan's older brother Er, Judah told Onan to have sexual intercourse with and impregnate Tamar, the widow of Er, so that the child or children could be declared to be Er's heir(s).[1] Onan had sex with Tamar, but performed coitus interruptus each time, spilling his "seed" (semen) on the ground, so that there would not be any offspring which he could not claim as his own.[2] The passage states that this displeased God, who killed Onan as punishment for disobedience.[3]...

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