Here you will find the Long Poem Genesis BK XX of poet Caedmon
(ll. 1248-1254) Then the sons of God began to take them wives from the tribe of Cain, a cursed folk, and the sons of men chose them wives from among that people, the fair and winsome daughters of that sinful race, against the will of God. Then the Lord of heaven lifted up His voice in wrath against mankind, and said: (ll. 1255-1262) "Lo! I have not been unmindful of the sons of men, but the tribe of Cain hath sorely angered Me. The sons of Seth have stirred My wrath against them; they have taken them wives from among the daughters of My foes. Woman's beauty and woman's grace and the eternal fiend have taken hold upon this people who dwelt of old in peace." (ll. 1263-1284) An hundred and twenty numbered winters in the world that fated folk were busied in evil. Then the Lord resolved to punish those faithless spirits, and slay the sinful giant sons, undear to God, those huge, unholy scathers, loathsome to the Lord. The King of victory beheld how great was the wickedness of men on earth, and saw that they were bold in sin and full of wiles. He resolved to bring destruction on the tribes of men, and smite mankind with heavy hand. It repented Him exceedingly that He had made man, and the first of men, when He created Adam. He said that for the sins of men He would lay waste the earth, and all that was upon the earth, destroying every living thing that breathed the breath of life. All this would the Lord destroy in the days that were coming on the sons of men. (ll. 1285-1295) But Noah, the son of Lamech, was good and dear to God, exceeding blessed, just and meek. And the Lord knew that virtue flourished in the heart of Noah. Wherefore God, the Holy Lord of every creature, spake unto Noah, declaring His wrath and vengeance on the sons of men. For He saw that the earth was full of wickedness, and its broad and fertile meadows filled with sin and defiled with uncleanness. And the Lord our God spake unto Noah, and said: (ll. 1296-1313) "I will destroy this people with a flood, man and every living thing that the air and the seas bring forth and nourish, birds of the air and beasts of the field. But thou, and thy sons with thee, shall have mercy when the black waters, the dark, destroying floods, shall overwhelm the hosts of sinful men. Begin to build thee a ship, a mighty seahouse, and in it make abiding-room for many, and set a rightful place for every tribe of earth. Build floors within the ark, dividing it in stories. And thou shalt build it three hundred cubits long and fifty cubits wide and thirty cubits high, and fasten it firmly against the might of the waves. And thou shalt take within the ark the seed of every living thing, and the offspring of all flesh upon the earth. And the ark must hold them all." (ll. 1314-1319) And Noah did according as God commanded him. He hearkened unto the Holy King of heaven, and began straightway to build the ark, a mighty sea-chest. And unto his kinsmen he proclaimed destruction coming upon men, and bitter vengeance. And they heeded him not. (ll. 1320-1326) Then after many winters the Faithful Lord beheld the greatest of ocean-houses, Noah's vessel, towering up, made tight with the best of pitch within and without against the floods. And it was best of all its kind, growing more hard the more the rough waves and the black sea-streams beat up against it.