Genesis 38:6-8

Darby Translation

⁶ And Judah took a wife for Er his firstborn, and her name was Tamar.

⁷ And Er, Judah's firstborn, was wicked in the sight of Jehovah, and Jehovah slew him.

⁸ Then Judah said to Onan, Go in to thy brother's wife, and fulfil to her the brother-in-law's duty, and raise up seed to thy brother.