8Enoch was the Great Grandfather of Noah. The Book of Enoch chapter 67:1 "And after that my great grandfather Enoch gave me all the secrets in the book and in the parables which had been given to him, and he put them together for me in the words of the book of the parables."This makes it possible for the Book to have survived the flood as its not too hard to accept that Noah would have taken his Great Grandfathers writings with him onto the ark. We first learn of Enoch in Genesis 5 but it leaves us with questions. Hebrews 11 has the answers and Jude quotes Enoch! How did Jude come to know the words of Enoch? They are not in the Bible. The answer of course, is The Book of Enoch. The quote in (Jude 14-15) & (1 Enoch 1:9) is as follows: "In the seventh (generation) from Adam Enoch also prophesied these things, saying: 'Behold, the Lord came with his holy myriads, to execute judgment on all, and to convict all the ungodly of all their ungodly deeds which they have committed in such an ungodly way, and of all the harsh things which ungodly sinners spoke against him'."