And Cain went out from the presence of the Lord. Cain is said to have departed from the presence of God, because, whereas he had hitherto lived in the earth as in an abode belonging to God, now, like an exile removed far from God's sight, he wanders beyond the limits of His protection. Or certainly, (which is not less probable,) Moses represents him as having stood at the bar of judgment till he was condemned: but now, when God ceased to speak with him, being freed from the sense of His presence, he hastens elsewhere and seeks a new habitation, where he may escape the eyes of God. The land of Nod [1] without doubt obtained its name from its inhabitant. From its being situated on the eastern side of Paradise, we may infer the truth of what was before stated, that a certain place, distinguished by its pleasantness and rich abundance of fruits, had been given to Adam for a habitation; for, of necessity, that place must be limited, which has opposite aspects towards the various regions of the world.

Footnotes

1 - "nvd signifies motion, flight, wandering, exile, and is the name of the region into which Cain was exiled." -- Schindler

The presence of the Lord - seems to have been at the entrance of the garden where the cherubim were stationed. There, probably, the children of men still lingered in faith and hope before the Lord, whom they still regarded as their Maker and merciful Saviour. They acknowledged his undeserved goodness in the form of sacrifice. The retreat of Cain from the scene of parental affection, of home associations, and of divine manifestation, must have been accompanied with many a deep, unuttered pang of regret and remorse. But he has deeply and repeatedly transgressed, and he must bear the consequence. Such is sin. Many a similar deed of cruelty and bloodshed might the sacred writer have recorded in the later history of man. But it is the manner of Scripture to note the first example, and then to pass over in silence its subsequent repetitions, unless when a particular transaction has an important bearing on the ways of God with man.

The land of Nod - As נוד nod signifies the same as נד sa , a vagabond, some think this verse should be rendered, And Cain went out from the presence of the Lord, from the east of Eden, and dwelt a vagabond on the earth; thus the curse pronounced on him, Genesis 4:12, was accomplished.

And Cain went out from the presence of the Lord,.... Either from the place where the Lord was talking with him; or from the place where his glorious Majesty usually resided, where was some visible token of his presence, some stream of light and glory which showed him to be there, and which was at the east of the garden of Eden; from whence Cain was obliged to go, not being suffered to appear any more before God, or among his worshippers: there was a place near Tripoli in Syria, near where Mount Lebanon ends, called , "the face of God", made mention of by Polybius (e), and Strabo (f): and was near those parts where some place the garden of Eden; and it is possible might have its name from some tradition that this was the place where the face of God was seen, or his presence enjoyed by our first parents after their ejection from Eden, and from whence Cain went forth:
and dwelt in the land of Nod; so called, not before he went there, but from his wandering up and down in it; continuing in no one place in it, as well as his mind was restless and uneasy; Jarchi mentions another reason of its name, that in every place where he went the earth shook under him, and men said, Depart from him, this is he that slew his brother:
on the east of Eden; further east from the place where his father Adam and his other children dwelt; not being allowed to continue any longer with them, or converse with them, after he had been guilty of so horrid a crime.
(e) Hist. l. 5. p. 260. (f) Geograph. l. 16. p. 519.

Cain cast off all fear of God, and attended no more on God's ordinances. Hypocritical professors, who dissemble and trifle with God, are justly left to themselves to do something grossly scandalous. So they throw off that form of godliness to which they have been a reproach, and of which they deny the power. Cain went out from the presence of the Lord, and we never find that he came into it again, to his comfort. The land Cain dwelt in was called the land of Nod, which means, 'shaking,' or 'trembling,' and so shows the restlessness and uneasiness of his own spirit, or 'the land of a vagabond:' they that depart from God cannot find rest any where else. Those on earth who looked for the heavenly city, chose to dwell in tabernacles or tents; but Cain, as not minding that city, built one on earth. Thus all who are cursed of God seek their settlement and satisfaction here below.

presence of the Lord--the appointed place of worship at Eden. Leaving it, he not only severed himself from his relatives but forsook the ordinances of religion, probably casting off all fear of God from his eyes so that the last end of this man is worse than the first (Matthew 12:45).
land of Nod--of flight or exile--thought by many to have been Arabia-PetrÃ&brvbr;a--which was cursed to sterility on his account.

The family of the Cainites. - Genesis 4:16. The geographical situation of the land of Nod, in the front of Eden (קדמת, see Genesis 2:14), where Cain settled after his departure from the place or the land of the revealed presence of God (cf. Jonah 1:3), cannot be determined. The name Nod denotes a land of flight and banishment, in contrast with Eden, the land of delight, where Jehovah walked with men. There Cain knew his wife. The text assumes it as self-evident that she accompanied him in his exile; also, that she was a daughter of Adam, and consequently a sister of Cain. The marriage of brothers and sisters was inevitable in the case of the children of the first men, if the human race was actually to descend from a single pair, and may therefore be justified in the face of the Mosaic prohibition of such marriages, on the ground that the sons and daughters of Adam represented not merely the family but the genus, and that it was not till after the rise of several families that the bands of fraternal and conjugal love became distinct from one another, and assumed fixed and mutually exclusive forms, the violation of which is sin. (Comp. Leviticus 18.) His son he named Hanoch (consecration), because he regarded his birth as a pledge of the renovation of his life. For this reason he also gave the same name to the city which he built, inasmuch as its erection was another phase in the development of his family. The construction of a city by Cain will cease to surprise us, if we consider that at the commencement of its erection, centuries had already passed since the creation of man, and Cain's descendants may by this time have increased considerably in numbers; also, that עיר does not necessarily presuppose a large town, but simply an enclosed space with fortified dwellings, in contradistinction to the isolated tents of shepherds; and lastly, that the words בנה ויהי, "he was building," merely indicate the commencement and progress of the building, but not its termination. It appears more surprising that Cain, who was to be a fugitive and a vagabond upon the earth, should have established himself in the land of Nod. This cannot be fully explained, either on the ground that he carried on the pursuits of agriculture, which lead to settled abodes, or that he strove against the curse. In addition to both the facts referred to, there is also the circumstance, that the curse, "the ground shall not yield to thee her strength," was so mollified by the grace of God, that Cain and his descendants were enabled to obtain sufficient food in the land of his settlement, though it was by dint of hard work and strenuous effort; unless, indeed, we follow Luther and understand the curse, that he should be a fugitive upon the earth, as relating to his expulsion from Eden, and his removal ad incertum locum et opus, non addita ulla vel promissione vel mandato, sicut avis quae in libero caelo incerta vagatur. The fact that Cain undertook the erection of a city, is also significant. Even if we do not regard this city as "the first foundation-stone of the kingdom of the world, in which the spirit of the beast bears sway," we cannot fail to detect the desire to neutralize the curse of banishment, and create for his family a point of unity, as a compensation for the loss of unity in fellowship with God, as well as the inclination of the family of Cain for that which was earthly.
The powerful development of the worldly mind and of ungodliness among the Cainites was openly displayed in Lamech, in the sixth generation. Of the intermediate links, the names only are given. (On the use of the passive with the accusative of the object in the clause "to Hanoch was born (they bore) Irad," see Ges. 143, 1.) Some of these names resemble those of the Sethite genealogy, viz., Irad and Jared, Mehujael and Mahalaleel, Methusael and Methuselah, also Cain and Cainan; and the names Enoch and Lamech occur in both families. But neither the recurrence of similar names, nor even of the same names, warrants the conclusion that the two genealogical tables are simply different forms of one primary legend. For the names, though similar in sound, are very different in meaning. Irad probably signifies the townsman, Jared, descent, or that which has descended; Mehujael, smitten of God, and Mahalaleel, praise of God; Methusael, man of prayer, and Methuselah, man of the sword or of increase. The repetition of the two names Enoch and Lamech even loses all significance, when we consider the different places which they occupy in the respective lines, and observe also that in the case of these very names, the more precise descriptions which are given so thoroughly establish the difference of character in the two individuals, as to preclude the possibility of their being the same, not to mention the fact, that in the later history the same names frequently occur in totally different families; e.g., Korah in the families of Levi (Exodus 6:21) and Esau (Genesis 36:5); Hanoch in those of Reuben (Genesis 46:9) and Midian (Genesis 25:4); Kenaz in those of Judah (Numbers 32:12) and Esau (Genesis 36:11). The identity and similarity of names can prove nothing more than that the two branches of the human race did not keep entirely apart from each other; a fact established by their subsequently intermarrying. - Lamech took two wives, and thus was the first to prepare the way for polygamy, by which the ethical aspect of marriage, as ordained by God, was turned into the lust of the eye and lust of the flesh. The names of the women are indicative of sensual attractions: Adah, the adorned; and Zillah, either the shady or the tinkling. His three sons are the authors of inventions which show how the mind and efforts of the Cainites were directed towards the beautifying and perfecting of the earthly life. Jabal (probably = jebul, produce) became the father of such as dwelt in tents, i.e., of nomads who lived in tents and with their flocks, getting their living by a pastoral occupation, and possibly also introducing the use of animal food, in disregard of the divine command (Genesis 1:29). Jubal (sound), the father of all such as handle the harp and pipe, i.e., the inventors of stringed and wind instruments. כּנּור a guitar or harp; עוּגב the shepherd's reed or bagpipe. Tubal-Cain, "hammering all kinds of cutting things (the verb is to be construed as neuter) in brass and iron;" the inventor therefore of all kinds of edge-tools for working in metals: so that Cain, from קין to forge, is probably to be regarded as the surname which Tubal received on account of his inventions. The meaning of Tubal is obscure; for the Persian Tupal, iron-scoria, can throw no light upon it, as it must be a much later word. The allusion to the sister of Tubal-Cain is evidently to be attributed to her name, Naamah, the lovely, or graceful, since it reflects the worldly mind of the Cainites. In the arts, which owed their origin to Lamech's sons, this disposition reached its culminating point; and it appears in the form of pride and defiant arrogance in the song in which Lamech celebrates the inventions of Tubal-Cain (Genesis 4:23, Genesis 4:24): "Adah and Zillah, hear my voice; ye wives of Lamech, hearken unto my speech: Men I slay for my wound, and young men for my stripes. For sevenfold is Cain avenged, and Lamech seven and seventy-fold." The perfect הרגתּי is expressive not of a deed accomplished, but of confident assurance (Ges. 126, 4; Ewald, 135c); and the suffixes in חבּרתי and פּצעי are to be taken in a passive sense. The idea is this: whoever inflicts a wound or stripe on me, whether man or youth, I will put to death; and for every injury done to my person, I will take ten times more vengeance than that with which God promised to avenge the murder of my ancestor Cain. In this song, which contains in its rhythm, its strophic arrangement of the thoughts, and its poetic diction, the germ of the later poetry, we may detect "that Titanic arrogance, of which the Bible says that its power is its god (Habakkuk 1:11), and that it carries its god, viz., its sword, in its hand (Job 12:6)" (Delitzsch). - According to these accounts, the principal arts and manufactures were invented by the Cainites, and carried out in an ungodly spirit; but they are not therefore to be attributed to the curse which rested upon the family. They have their roots rather in the mental powers with which man was endowed for the sovereignty and subjugation of the earth, but which, like all the other powers and tendencies of his nature, were pervaded by sin, and desecrated in its service. Hence these inventions have become the common property of humanity, because they not only may promote its intended development, but are to be applied and consecrated to this purpose for the glory of God.

And Cain went out from the presence of the Lord, and dwelt on the east of Eden - Somewhere distant from the place were Adam and his religious family resided: distinguishing himself and his accursed generation from the holy seed; in the land of Nod - That is, of shaking or trembling, because of the continual restlessness of his spirit. Those that depart from God cannot find rest any where else. When Cain went out from the presence of the Lord, he never rested after.