Eliphaz was the first-born son of Esau

Esau

Esau , in the Hebrew Bible, is the oldest son of Isaac. He is mentioned in the Book of Genesis, and by the minor prophets, Obadiah and Malachi. The New Testament later references him in the Book of Romans and the Book of Hebrews....

 by his wife Adah. He had six sons, one of whom was Amalek

Amalek

The Amalekites are a people mentioned a number of times in the Hebrew Bible. They are considered to be descended from an ancestor Amalek....

, born to his concubine Timna, who was the ancestral enemy of the Israel

Israel

The State of Israel is a parliamentary republic located in the Middle East, along the eastern shore of the Mediterranean Sea...

ite people (Exodus 17:16; Deuteronomy

Deuteronomy

The Book of Deuteronomy is the fifth book of the Hebrew Bible, and of the Jewish Torah/Pentateuch...

 25:19).

The Midrash

Midrash

The Hebrew term Midrash is a homiletic method of biblical exegesis. The term also refers to the whole compilation of homiletic teachings on the Bible....

 relates that when Jacob

Jacob

Jacob "heel" or "leg-puller"), also later known as Israel , as described in the Hebrew Bible, the Talmud, the New Testament and the Qur'an was the third patriarch of the Hebrew people with whom God made a covenant, and ancestor of the tribes of Israel, which were named after his descendants.In the...

 escaped from Esau and fled to his uncle Laban

Laban (Bible)

Laban is the son of Bethuel, brother of Rebekah and the father of Leah and Rachel and Bilhah and Zilpah as described in the Book of Genesis. As such he is brother-in-law to Isaac and both father-in-law and uncle to Jacob...

 in Haran

Haran (biblical place)

Ḥaran, Charan, or Charran is a Biblical place. Haran is almost universally identified with Harran, an Assyrian city whose ruins are in present-day Turkey. In the Hebrew Bible, the name first appears in the Book of Genesis, in the context of Patriarchal times...

, Esau sent Eliphaz to pursue and kill Jacob. When they met Jacob implored Eliphaz not to kill him, but Eliphaz challenged that he had his father's instructions to fulfill. Jacob gave everything he had with him to Eliphaz and said, "A poor person is as good as dead." Eliphaz was satisfied and left his uncle naked and penniless, but still alive. (Rashi

Rashi

Shlomo Yitzhaki , or in Latin Salomon Isaacides, and today generally known by the acronym Rashi , was a medieval French rabbi famed as the author of a comprehensive commentary on the Talmud, as well as a comprehensive commentary on the Tanakh...

 to Genesis 29:11)