What Happens in Genesis 38? Judah, Tamar, Onan, and the Lessons on Sin and Redemption
In Genesis 38, Judah, one of the sons of Jacob (Israel), sleeps with his daughter-in-law, Tamar, who becomes pregnant. His son, Onan, spilled his semen on the ground, and this is displeasing to God. The sin of Onanism is one interpretation of these events. Catholics must be chaste.
Tamar is one of four women mentioned in the genealogy of Jesus. She was in disguise as a harlot when she slept with her father-in-law; she had twins. Did you think Jesus could be descended from such a broken family?
Genesis 38 Summary
Judah is one of the twelve sons of Jacob (Israel). He was the fourth of the sons, and his name means praise. Therefore, whenever the country of Israel went into battle, the tribe of Judah went first. He had three sons, Er, Onan, and Shelah. Er died after he married Tamar.
After Er died, Onan was told to sleep with her produce an heir. He refused, so Judah promised his third son, Shelah, though he failed to keep this promise. Tamar, disguised as a prostitute, went to Judah, who slept with her. She became pregnant and had twins.
Onan had spilled his seed on the ground, thereby separating the unitive act of sex from the procreative act of sex. This led to the definition of Onanism in later interpretations. This is very important and of cultural and modern relevance.
Cultural Relevance

When one thinks about the main things Catholics need to do, what is written in Genesis 38 is of great cultural relevance. The sin of Onanism has been in movies. Such as in Monty Python’s “Meaning of Life,” “Every sperm is sacred, every sperm is great, if a sperm gets wasted, God gets quite irate.” This practice among Catholics affects many relationships and creeps into modern culture in many ways.
Modern Relevance
The definition of the sin of Onanism is why Catholics cannot masturbate, have sex out of wedlock, or have sex outside of the desire to have children, the procreative act. Genesis 38 has been interpreted as the first mention of this sin in the Bible. The need for Catholics to be chaste is mentioned several more times, including by Jesus.
Also important is the fact that Judah got his daughter-in-law pregnant. His sin, inside the family of Jesus, signifies that God can do miraculous things, even in the face of brokenness and sin.
Parting Shots
All of this brokenness in the genealogy of Jesus is an example of how he can write straight with crooked lines. The several sins of Judah and Tamar in the direct line of Jesus show that God can even bring extreme goodness when there is extreme brokenness. This chapter in the book of Genesis is important because the sin of Onanism is defined from these events. This is the sin of a male ejaculating for any other reason than for procreation.
Disclaimer:This article contains a summary of Genesis 38 as well as interpretive insights from the author. Interpretations of biblical texts can differ, and this piece represents one approach to understanding the passage.
