Women in the Bible often face oppression from the patriarchal Jewish culture that strictly controlled females' access to sex and marriage to assure tribal purity in procreation. This arrangement often allowed men to engage in extramarital sex and renege on their marriage promises, while women were bound by the strictures that men set up. An Old Testament widow named Tamar outsmarted this sexual system.
Tamar's Story Is a Morality Play
Genesis 38 tells the story of Tamar, her two husbands, Er and Onan, and her father-in-law Judah. According to footnotes in The Oxford Annotated Bible with Apocrypha, the story is intended to show the parts that several people played in fulfilling God's promise to Abraham that he would have many descendants. In addition, the story serves as a morality play about the virtue of keeping one's promises, but it also tells how Hebrew women might have outwitted men by turning their own cultural practices against them.
Judah and the 12 Tribes of Israel
Judah was one of Jacob's 12 sons, the men who became the progenitors of the 12 tribes of Israel. The scripture says that Judah moved away from Jacob's camp after he and his brothers sold their younger sibling Joseph into slavery, and tricked their father into thinking Joseph had been eaten by a wild animal.
Judah - A Man's Name and a Place Name
Judah resettled near Bethlehem and married the daughter of a man named Shua, a Canaanite. Judah and his unnamed wife had three sons: Er, Onan and Shelah. The tribe that descended from them was also named Judah, as was the land where they dwelled.
Judah's Son Er Marries Tamar
Genesis 38:6 says that "Judah took a wife for Er, his firstborn; her name was Tamar." Unfortunately, Er died shortly after their marriage. Scripture says only that Er was "wicked" and therefore God struck him dead -- pre-scientific explanation for a sudden death. The person was presumed to have done evil, because otherwise God would have let him live a long time and have many children.
Judah's Son Onan Marries Tamar
Judah then ordered his second eldest son, Onan, to marry and impregnate Tamar "to raise up offspring for your brother." This custom of marrying a deceased brother's widow for the sake of continuing his family line is know as a "levirate marriage," outlined in Deuteronomy 25:5-10. This type of marriage apparently was a longtime tribal practice before it was codified into law.
However, Onan knew that any child he fathered with Tamar in this way would legally be considered his brother Er's children, not his. So instead of impregnating Tamar, Onan "spilled his seed upon the ground," meaning either that he withdrew from copulation at the time of orgasm (coitus interruptus), or that he masturbated. These interpretations led to both coitus interruptus and masturbation being referred to as "onanism" for at least three centuries before the practices were named scientifically.
Onan's crude method of birth control incurred divine wrath, so scripture says, with the result that he also died suddenly.
Judah Fears the Power of Tamar
By now Judah was spooked; two of his sons had died as a result of having sexual relations with Tamar. A footnote to Genesis 38:11 says that Judah apparently feared that Tamar had some kind of sinister power. Nonetheless, Judah asked Tamar to return to her father and remain a widow until his youngest son Shelah came of age, at which time Shelah would marry Tamar in order to fulfill the levirate marriage practice.
Judah Reneges on His Promise to Marry His Son Shelah to Tamar
However, by the time that Shelah was an adult, Judah showed no inclination to keep his promise to marry his surviving son to Tamar. Recognizing her plight, Tamar decided to take matters into her own hands.
Tamar Conceives Her Plot
After his wife died, Judah and his friend Hirah the Adullahmite went to a nearby town to shear their sheep and sell the wool. Genesis 38:14 tells that upon learning of this trip, Tamar took off her widow's garments, put on her finest clothes, veiled her face, and sat outside a gate on the way to town. Judah saw her there and assumed she was a temple prostitute.
Not recognizing his widowed daughter-in-law in her veil and finery, Judah approached Tamar, but he had no money. Instead he promised Tamar a young goat from his flock, but she bargained for "a pledge," consisting of Judah's symbols of tribal authority: his signet ring, his belt and his staff. Judah consented and had sex unknowingly with his daughter-in-law, who conceived from the encounter.
Returning home, Judah sent a young goat to town for the prostitute, but she was gone. All Judah could do was let the "prostitute" keep his things.