Verses with the word er in the Old Testament (7 verses):

Genesis 38:3
And she conceived, and bare a son; and he called his name Er.

Genesis 38:6
And Judah took a wife for Er his firstborn, whose name was Tamar.

Genesis 38:7
And Er, Judah's firstborn, was wicked in the sight of the LORD; and the LORD slew him.

Genesis 46:12
And the sons of Judah; Er, and Onan, and Shelah, and Pharez, and Zarah: but Er and Onan died in the land of Canaan. And the sons of Pharez were Hezron and Hamul.

Numbers 26:19
The sons of Judah were Er and Onan: and Er and Onan died in the land of Canaan.

1 Chronicles 2:3
The sons of Judah; Er, and Onan, and Shelah: which three were born unto him of the daughter of Shua the Canaanitess. And Er, the firstborn of Judah, was evil in the sight of the LORD; and he slew him.

1 Chronicles 4:21
The sons of Shelah the son of Judah were, Er the father of Lecah, and Laadah the father of Mareshah, and the families of the house of them that wrought fine linen, of the house of Ashbea,