Genesis 4:17

Cain knew his wife. The sudden mention of Cain’s wife creates no problem. Chapter 5:4 states that Adam “begat sons and daughters” besides the three sons whose names are given. The earliest inhabitants of earth had no other choice than to marry their brothers and sisters in order to fulfill the divine command, “Be fruitful and multiply” (see Acts 17:26). That the custom long remained in vogue is seen in Abraham’s marriage to his half sister Sarah. Such marriages were later prohibited (see Lev. 18:6-17).

She conceived, and bare Enoch. That God did not withhold offspring from the disobedient and reprobate Cain is another evidence of His merciful character (Ps. 145:9; Matt. 5:45). The name “Enoch” may mean “dedication” or “consecration” it may also mean “initiation.” Perhaps the name Cain gave his son indicated his intention to begin living his life as he pleased. Luther thought the mother may have selected the name Enoch, thereby expressing hope that the child might be an augury of blessing for their saddened home.

He builded a city. Literally, “he began to build.” This was probably no more than an attempt to erect a fortified camp for his family as a more or less permanent place of abode. This suggests that Cain may not have had much confidence in God’s assurance of protection. It is possible also that his attempt to found a city may have been dictated by a desire to bid defiance to the curse that doomed him to a wandering life.

It is worthy of note that the world’s first “city” was founded by the world’s first murderer, a perversely impenitent individual whose life, wholly and hopelessly dedicated to evil, was spent in defiance of God. God’s plan that man should live amid nature and behold in it the Creator’s might and power was in this way thwarted. Many present-day evils are the direct result of the unnatural gathering together of human beings into great cities, where man’s worst instincts bear rule, and vice of every type flourishes.

The name of the city. In naming this city after his son Enoch, “dedication” or “initiation,” Cain apparently consecrated it to the realization of his sinful ambitions.