The Second Book of Adam and Eve 12
1THEN Seth, the just, called his son Enos, and Cainan, son of Enos, and Mahalaleel, son of Cainan, and said unto them:--
2"As my end is near, I wish to build a roof over the altar on which gifts are offered."
3They hearkened to his commandment and went out, all of them, both old and young, and worked hard at it, and built a beautiful roof over the altar.
5Then when the building of the roof was completed, he commanded them to make offerings. They worked diligently at these, and brought them to Seth their father who took them and offered them upon the altar; and prayed God to accept their offerings, to have mercy on the souls of his children, and to keep them from the hand of Satan.
6And God accepted his offering, and sent His blessing upon him and upon his children. And then God made a promise to Seth, saying, "At the end of the great five days and a half, concerning which I have made a promise to thee and to thy father, I will send My Word and save thee and thy seed."
See also: The First Book of Adam and Eve 3:6
8But Seth abode in the Cave of Treasures, a few days, and then suffered--sufferings unto death.
10Then Seth prayed over them, and blessed them, and adjured them by the blood of Abel the just, saying, "I beg of you, my children, not to let one of you go down from this Holy and pure Mountain.
See also: The First Book of Adam and Eve 79:10
11Make no fellowship with the children of Cain the murderer and the sinner, who killed his brother; for ye know, O my children, that we flee from him, and from all his sin with all our might because he killed his brother Abel."
12After having said this, Seth blessed Enos, his first-born son, and commanded him habitually to minister in purity before the body of our father Adam, all the days of his life; then, also, to go at times to the altar which he Seth had built. And he commanded him to feed his people in righteousness, in judgment and purity all the days of his life.
14Then they wound up the body of Seth, and embalmed him with sweet spices, and laid him in the Cave of Treasures, on the right side of our father Adam's body, and they mourned for him forty days. They offered gifts for him, as they had done for our father Adam.
15After the death of Seth Enos rose at the head of his people, whom he fed in righteousness, and judgment, as his father had commanded him.
16But by the time Enos was eight hundred and twenty years old, Cain had a large progeny; for they married frequently, being given to animal lusts; until the land below the mountain, was filled with them.