Onan

Biblical account

After Yahweh slew Onan's oldest brother Er, Judah instructed Onan to enter a levirate marriage with Tamar to provide her with offspring. Religion professor Tikva Frymer-Kensky noted the economic implications: any son born to Tamar would be deemed Er's heir and could claim the firstborn's double inheritance share, whereas if Er died childless or with only daughters, Onan would inherit as the oldest surviving son. When Onan had sex with Tamar, he withdrew before ejaculation, spilling his seed on the ground, because any child would not legally be his heir.

The Bible states that Onan displeased Yahweh, so the Lord slew him. Biblical scholars generally agree that Onan's death resulted from his refusal to fulfill the levirate obligation, not from masturbation. The regulation of levirate marriage in Deut 25:7–10 indicates the custom faced opposition, with the halizah ceremony allowing a man to refuse his duty as a concession to reluctance.

Interpretation

However, Leviticus prescribes only ritual washing and temporary impurity until evening for ejaculation, whether from intercourse or not. Early Christian writers often focused on the spilling of seed and non-procreational sexual acts. Jerome argued against such practices, and Epiphanius of Salamis condemned heretics using coitus interruptus, calling it the sin of Onan. Clement of Alexandria reflected an early Christian abhorrence of spilling seed without explicit reference to Onan.

The 1930 papal encyclical Casti connubii invoked the biblical text, quoting Augustine that intercourse preventing conception is unlawful and wicked, citing Onan. John Calvin in his Commentary on Genesis called voluntary spilling of semen outside intercourse monstrous and deliberate withdrawal for that purpose doubly monstrous. Methodism founder John Wesley believed any waste of semen in unproductive sexual acts, whether masturbation or coitus interruptus as with Onan, destroyed the souls of practitioners.

He wrote Thoughts on the Sin of Onan (1767) and later A Word to Whom it May Concern (1779) to censor a work by Samuel-Auguste Tissot, warning about the physical and mental dangers of self-pollution.

Did You Know?

• Many modern languages derive words for masturbation from Onan's name, including Hebrew (אוננות, onanút), German (Onanie), Greek (αυνανισμός, avnanismós), Japanese (オナニー, onanī), and Swedish (onani).
• The Merriam-Webster online dictionary defines onanism as masturbation, coitus interruptus, or self-gratification.
• The Talmud likens emitting semen in vain to shedding blood.