There is a clear parallel between the situation of Cain and that of his father Adam. They have disobeyed to God and they find themselves in the east of Eden. Among other things, the phrase appears somewhat strange here, for Adam and Eve were already in the east of the garden of Eden (Gen 3:14). Both of them live outside the place where man was originally placed by God, a heavenly place because there man was in communion with God, with other men, and with Mother Earth. In this verse, the coincidence of meanings on the east of Eden / out from the presence of Lord is clear and evident: Cain moves away from the Lord / he lives in the east of Eden. In these chapter there is a clear progression. In fact, Adam was driven out of the garden of Eden, that is, from the heart, from the most intimate region of communion with God, while Cain simply moved away from Eden, or from the region where paradise stood.
In this way, man is now totally outside the orbit of communion with God. This element is also well-documented in the verse. Adam was expelled from Eden’s garden (Gen 3:14). God did not throw Cain out, because Cain was already out of the most intimate communion with him (i.e. out of the Eden’s garden). However, because of his actions, he went even further, in full freedom and awareness. Cain is the image of every man who does the horrible act of killing another man. God continues to protect him, but Cain is constantly in agitation and he feels himself far from God. An apparent contradiction that raises anger and frustration.
He will dwell on the mysterious village of Nod, impossible to locate on the map. As elsewhere in these first chapters of Genesis, the author is not interested in details. He simply wants to communicate a message that comes from the similarity of consonants between Nod and Nad. In fact, the first name is the place that cannot be traced, the second name (cf. Gen 4:12) is an adjective that means fugitive, wandering, without peace.
Whoever kills someone is not killed by God, who continues to support him as any other human being. Whoever kills a man lives in the country called without peace, without dwelling. Such a man lives in a state of continuous agitation, especially if – as Cain – he recognizes the wrong action he have committed: killing another man.