Jamieson, Fausset and Brown on Jeremiah 49:8

8. turn--namely, your backs in flight.

dwell deep--in deep defiles and caves [Grotius], which abound in Idumea. Others refer it to the Arab custom of retiring into the depth of the desert when avoiding an offended foe (Jr 49:30).

Dedan--a tribe bordering on and made subject by Idumea; descended from Jokshan, son of Abraham and Keturah (Ge 25:1-3).

Esau--The naming of Edom's progenitor, reprobated by God, recalls the remembrance of the old curse on him for his profanity, both his sin and its punishment being perpetuated in his descendants (He 12:16, 17).