Genesus 4:8
6 Then the Lord said to Cain, “Why are you angry, and why is your expression downcast? 7 Is it not true that if you do what is right, you will be fine? But if you do not do what is right, sin is crouching at the door. It desires to dominate you, but you must subdue it.” 8 Cain spoke to his brother Abel.21 While they were in the field, Cain attacked his brother Abel and killed him.
Genesis 25:29
28 Isaac loved Esau because he had a taste for fresh game, but Rebekah loved Jacob. 29 Now Jacob cooked some stew, and when Esau came in from the open fields, he was famished. 30 So Esau said to Jacob, “Feed me some of the red stuff—yes, this red stuff—because I’m starving!” (That is why he was also called Edom.)
Notes and References
"... The appearance of the same extraneous detail in both stories of brother killing brother does not seem accidental, especially in light of all the other evidence indicating that these two stories belong to a single author’s work. And there is further evidence of their linkage, because references to “field” occur in other sibling rivalry stories in these texts as well. In the famous story of Jacob’s appropriation of Esau’s birthright, Esau comes to Jacob “from the field” (Genesis 25:29). Indeed, Esau is introduced as “a man who knew hunting, a man of the field” (verse 27) ..."
Friedman, Richard Elliott The Hidden Book in the Bible (pp. 42-43) Harper San Francisco, 1998