What was Er's sin?

Question

In response to this question asked by JonEricson.

Genesis 38:6-11 (NJPS):

Judah got a wife for Er his first-born; her name was Tamar. But Er, Judah’s first-born, was displeasing to the Lord, and the Lord took his life.

This is a strange and unique passage in the Bible. What was "displeasing" about Er? Why doesn't the Bible tell us? What are the literary implications of this passage and how should we understand it?

Answer 1

While researching my answer to Jon's question I came across the following rabbinic interpretation (Babylonian talmud, Yevamot 34b):

[The source for] Onan's [guilt] may well be traced, for it is written in Scripture, That he spilt it on the ground; whence however, [that of] Er? -R. Nahman b. Isaac replied: It is written, And He slew him also, he also died of the same death.

The rabbis understand "slew him also", without elaboration, to mean "slew him also for the same reason": Er prevented Tamar from becoming pregnant.

Why would he do that? The talmud continues:

[The reason for] Onan's [action] may well be understood, because he knew that the seed would not be his; but why did Er act in such a manner? — In order that she might not conceive and thus lose some of her beauty.

So according to the rabbis Er and Onan both prevented Tamar from conceiving; they acted for different (selfish) reasons, but this act against their wife was deserving of punishment.

Answer 2

In the end, the focus is less on Er than it is on Judah and Tamar. Judah was stealing Tamar's rightful due, namely a sin and support mechanism. What Er did was irrelevant to the focus the author wished to place on Judah's bad behavior. For more on Tamar and Judah, check out:

• Why was Tamar more righteous than Judah

• Did God really kill Onan for masturbating?

In a strictly nationalistic sense, Judah is the primary kingdom of the South, and Joseph the hero of the North (Ephraim is Joseph's son), it is interesting how bad of a light the south is shown in this story. It would seem to be evidence for a more Northerly bias on the part of the writer(s) of Genesis.

Answer 3

The text is obviously ambiguous on this point and I agree with AffableGreek that Er isn't the focus of the story.

However...

Firstborns don't do well in the Pentateuch:

• Cain is made to be a wanderer (4:11)
• Ishmael is excluded from the Abrahamic covenant
• Esau is excluded from the Abrahamic covenant
• Reuven, Gad, and Menasheh, all firstborns, take up residence to the west of the Jordan river, outside of the Land of Israel proper (32:33)

The story of Judah and Tamar emphasizes that Er was a firstborn:

Judah got a wife for Er, his firstborn, and her name was Tamar. But Er, Judah’s firstborn, was wicked in the LORD’s sight; so the LORD put him to death (NIV 38:6-7).

The story does not tell us what Er did to be killed, but the Bible highlights a pervasive theme by implying: Er was displeasing before the Lord because he was a firstborn.