We know that in the initial design of the creation of the Lord God the life of man would always be, and eternally in the presence of Him without sin. And we also know now that the infinite love of the Lord God for the life of this man is eternal, and thus allowed its continuity. Man received teachings that could lead him to live, so that he might multiply and fill the earth and people it abundantly: "And God blessed them, and God said unto them, Be fruitful and multiply and fill the earth...” (Genesis 28:1a).
By the guidance of the Lord Yahweh after sin, the wife would have children: “ And he said unto the woman, I will greatly increase thy pain, and thy conception: thou shalt bear children with pain.... (Genesis 3:16a), so he met Adam and Eve his wife and had children: “ And Adam met Eve his wife, and she conceived, and had Cain, and said, I've reached the Lord a man. ” (Genesis 4:1).
Eva conceived and had Cain, and showed gratitude, for he exalted the name of the Lord God, and honored the Lord by saying, "Acquaint a man from the Lord." With the birth of Cain, Abel was also born: “ And there was more to your brother Abel: and Abel was a shepherd of sheep, and Cain was a farmer of the earth..” (Genesis 4:2). At the time of the growth of these two boys of course there was a long time for Adam to talk about life in paradise and events, and also all the teachings received from the Lord God, also today they lived in sin devoid of glory and eternal life, and for this they must walk according to a new project of life.