In this chapter אֲדָמָה (ground), שָׂדֶה (field), and אֶ֫רֶץ (earth, in this chapter) all occur. אֲדָמָה is the most frequent land word in this chapter.
At the beginning of this chapter Cain is the worker of the ground (4:2-3). Cain’s occupation is to cultivate the ground, but as the story unfolds he murders his brother in the field—in the place of cultivation. Because Abel’s blood cries to God from the ground, the ground figures prominently in Cain’s punishment. He is cursed from the ground, which means that the ground will no longer produce for him. In addition Cain is exiled from his land and becomes “a fugitive and a wanderer on the earth” (4:12). We see in this account something that will be expanded upon in the Mosaic code: murder pollutes the land. To avoid the consequences of polluted land, the law will set up mechanisms for dealing with the pollution.
In many ways the punishment of Cain is an intensification of the punishment received by Adam. The ground was cursed such that it would require extra work from Adam to make it productive; Cain is cursed (the person, not the ground this time) such that the ground will not produce for him. Adam and Eve were exiled from Eden, and at the eastern edge of the garden cherubim blocked the entrance; Cain is exiled from his land and moves further east of Eden to the land of wandering (Nod). This exile in both cases involves moving from the presence of God.
In these opening chapters of Genesis land plays an important role in the punishments given. This is likely due to the prominent place it holds in relation to God’s blessing and to the duty of man.
 Leupold, 1:206; Wenham, WBC, 1:107.
 Calvin, Genesis, 209.
 Mathews, NAC, 1:275-76; Craig G. Bartholomew, Where Mortals Dwell: A Christian View of Place for Today (Grand Rapids: Baker, 2011), 33-34.
 Wenahm, WBC, 1:108.
 Currid, EPSC, 1:151.
 Matthews, NAC, 1:278.