Bereshis 38:6-8

Orthodox Jewish Bible

⁶ And Yehudah took a wife for Er his bechor, whose shem was Tamar.

⁷ And Er, bechor Yehudah, was rah in the eyes of Hashem; and Hashem slaughtered him.

⁸ And Yehudah said unto Onan, Go in unto eshet achicha, and enter into levirate marriage with her, and raise up zera to achicha.