Another discovery among the Dead Sea Scrolls in Qumran, the Damascus document is a curious text that sums up the creed, background and beliefs of a community of Jews who had separated themselves from other Jews who they believed would be judged by God for not staying true to their God and His Torah.
While giving examples from Jewish history of ones who had followed their own hearts instead of following after God’s righteousness, the Damascus document mentions the ‘Guardian Angels’ who fell and their giant sons, who also fell for the same reason.
Thus, according to the writer of the text, Noah’s flood destroyed them all.
the Damascus Document’s Story of Guardian Angels who fell and their Giant Sons
So now, my children, listen to me that I may uncover your eyes to see and to understand the deeds of God, choosing what pleases Him and hating what He rejects, living perfectly in all His ways, not turning away through thoughts caused by the sinful urge and lecherous eyes.
For many have gone astray by such thoughts, even strong and doughty men of old faltered through them, and still do.
When they went about in their willful heart, the Guardian Angels of Heaven fell and were ensnared by it, for they did not observe the commandments of God.
Their sons, who were as tall as cedars, and whose bodies were as big as mountains, fell by it.
Everything mortal on dry land expired and became as if they had never existed, because they did their own will, and did not keep the commandments of their Maker, until finally His anger was aroused against them.
Damascus document 2:16 – 19
More information
From The Dead Sea Scrolls: A New Translation, by Michael Wise, Martin Abegg, and Edward Cook (rev. ed., Harper San Francisco, 2005). (4) The Damascus Document (CD) (2005) | Edward Cook – Academia.edu