Onan was the second son of Judah, son of Jacob. God killed him because he did not fulfill his brotherly duty. Onan was greedy and had no respect for his deceased brother or sister-in-law.
In the time of Judah and Onan, if a man died without having children, his relative would most likely take his wife so she could become pregnant. The woman’s first child would be the dead man’s heir, because the wife did not inherit ( Deuteronomy 25: 5-6 ).
Onan’s older brother, Er, married a woman named Tamar. But Er was wicked, so God killed him ( Genesis 38: 6-7 ). Er had no children, so Tamar was given to Onan. When Onan slept with Tamar, he spilled the semen on the floor, so she would not get pregnant, because he did not want his brother to have heirs. So God killed Onan too ( Genesis 38: 8-10 ).
Was Onan’s sin masturbation?
No, Onan’s sin was not masturbation. The Bible says that Onan’s sin was not wanting to give descendants to his brother. Tamar’s first son with Onan would be considered “a descendant” of Er, because he was his heir. Onan was not masturbating. He interrupted coitus to prevent Tamar from having children.
See also: What does the Bible say about masturbation?
Why did God kill Onan?
God killed Onan because what he was doing was so cruel. At that time, the eldest son received a greater inheritance than all the other brothers ( Deuteronomy 21:17 ). Since Er died childless, the oldest son’s inheritance would go to Onan when Judah died. But if Tamar had a son, the inheritance would go to that child and not Onan.
Onan acted out of greed. He could have refused to marry Tamar, giving responsibility to his younger brother or another close relative ( Deuteronomy 25: 7-9 ). But he decided to marry Tamar and make sure she had no children!
Onan did not care about Tamar. He took advantage of her but denied her what was most important to a woman at that time: a son. There were no job opportunities for women. If a woman had no children, she would receive no inheritance and would have no one to look after her in her old age. Onan was condemning Tamar to misery!
Onan’s greed blinded him. He was willing to do anything to keep the money, even if it meant destroying a woman’s life and disrespecting his brother’s memory. His heart was corrupted, so God punished him.