Genesis 6:1
1 When humankind began to multiply on the face of the earth, and daughters were born to them, 2 the sons of God saw that the daughters of humankind were beautiful. Thus they took wives for themselves from any they chose. 3 So the Lord said, “My Spirit will not remain in humankind indefinitely, since they are mortal. They will remain for 120 more years.” 4 The Nephilim were on the earth in those days (and also after this) when the sons of God would sleep with the daughters of humankind, who gave birth to their children. They were the mighty heroes of old, the famous men.
1 Enoch 6:1
1 And it came to pass when the children of men had multiplied that in those days were born unto them beautiful and comely daughters. 2 And the angels, the children of the heaven, saw and lusted after them, and said to one another: 'Come, let us choose us wives from among the children of men and beget us children.' 3 And Semjâzâ, who was their leader, said unto them: 'I fear ye will not indeed agree to do this deed, and I alone shall have to pay the penalty of a great sin.'
Notes and References
"... 1 Enoch 6:1-2 agrees with Genesis 6:1-2 in many details, the first of which is vocabulary and the second is context. The amount of verbal correspondences is seen in the heavy underlining of the texts adjacent to one another in the section heading above. There is no doubt, due to the high density of correspondence, that the Enochic author is here basing his narrative about the “sons of heaven” on his understanding and interpretation of the Genesis text and tradition. The fact that so many words are taken almost exactly from Genesis in this passage and several following it argues that the author of 1 Enoch 6 was aware of the text of Genesis, not just simply the tradition that is presumably behind it ..."
Townsend, Colby J. The Use of Scripture in 1 Enoch 1-36 (p. 70) University of Utah, 2016