Onanism: What the Bible Actually Condemns

Onanism: What the Bible Actually Condemns

Few passages have been more misunderstood in church history than Genesis 38:8–10. Onan, Judah’s son, refuses to fulfill his duty toward Tamar, and the Lord strikes him down. For centuries, this passage has been used to condemn masturbation or all forms of birth control. But what does the Bible actually say? A careful look shows that Onan’s sin was rebellion against covenant duty, not simply the physical act itself.

The Text

Genesis 38:8–10 (NASB): “Then Judah said to Onan, ‘Have relations with your brother’s wife, and perform your duty as a brother-in-law to her, and raise up a child for your brother.’ Now Onan knew that the child would not be his; and when he had relations with his brother’s wife, he wasted his seed on the ground so that he would not give a child to his brother. But what he did was displeasing in the sight of the Lord; so He took his life also.”

The context is levirate duty—a cultural and later legal requirement (codified in Deuteronomy 25:5–10) for a brother to provide offspring for his deceased brother’s widow. Onan’s refusal was an act of selfish rebellion. He wanted the sexual privilege without the covenant responsibility.

Misconception: “Onanism = Masturbation”

Church tradition sometimes turned this into a blanket condemnation of self-stimulation. But that confuses categories. Onan’s sin was not private sexual failure; it was covenant treachery. He denied Tamar justice, denied his brother a legacy, and by extension opposed God’s covenant promise.

A common misconception is that because Onan “spilled his seed on the ground” (Genesis 38:9), God condemned all forms of birth control. But Scripture does not say this. Nowhere in the Bible is there a command forbidding contraception. Onan was judged not for practicing “birth control,” but for refusing to fulfill his covenant obligation of levirate marriage. His sin was selfish rebellion—using Tamar for pleasure while denying her justice and denying his brother an heir. The text is about covenant faithfulness, not a blanket ban on family planning.

Theological Reflection

God judged Onan not for a solitary act but for his rebellion against family and covenantal responsibility. The lesson is not about mechanics but about faithfulness. God cares about the heart that refuses obedience while still seeking personal gratification.

Conclusion

Onan’s story warns against using God’s gifts for selfish gain while despising His commands. It is not about masturbation or contraception, but about covenant faithfulness. The takeaway is that God expects His people to honor their commitments, not manipulate His blessings for personal advantage.