Who are the Nephilim in Genesis 6 ?

Genesis 6:1-5

Now it came to pass, when men began to multiply on the face of the earth, and daughters were born to them, that the sons of God saw the daughters of men, that they were beautiful; and they took wives for themselves of all whom they chose. And the LORD said, “My Spirit shall not strive with man forever, for he is indeed flesh; yet his days shall be one hundred and twenty years.” There were giants (Nephilim) on the earth in those days, and also afterward, when the sons of God came in to the daughters of men and they bore children to them. Those were the mighty men who were of old, men of renown.

The sons of God refers to the descendants of Seth, while the daughters of men refers to the descendants of Cain. The righteous line of Seth intermarried with the unrighteous line of Cain resulting in the corruption of society.

Several statements in Genesis about Seth’s descendants indicate that sons of God applies to them.

Genesis 4:26

To Seth, to him also a son was born; and he called his name Enosh. Then men began to call upon the name of the Lord.

Genesis 5:24

Enoch walked with God; and he was not, for God took him.

Genesis 6:8

But Noah found favor in the eyes of the Lord.

Adam was created in God’s image and that Seth was begotten in Adam’s image. The implication is that the line of Adam through Seth constitutes the Sons of God. 

Genesis 5:1-3

This is the book of the generations of Adam. In the day when God created man, He made him in the likeness of God. He created them male and female, and He blessed them and named them Man in the day when they were created. When Adam had lived one hundred and thirty years, he became the father of a son in his own likeness, according to his image, and named him Seth.

The line of Cain 

Cain is driven out from the presence of God. 

Lamech, a descendant of Cain, takes two wives, contrary to the standard established in the garden. 

When Cain murders his brother, God confronts him with his deed. 

When Lamech commits murder, the absence of God is painfully obvious. 

Cain laments that his punishment is too great to bear. 

Lamech boasts that he is able to take care of himself — he doesn’t need God’s protection. 

The primary characterization of Cain’s line is that they were becoming increasingly separated from God. The godly line, who were supposed to walk with God, saw the daughters from the ungodly line. 

Some hold the view that the Nephilim are mutants; half demon/half human. However, this can’t be true because demons (fallen angels) are nonsexual, nonphysical beings who are incapable of having sexual relations and producing offspring. 

Angels don’t marry

Mark 12:24-27

Jesus answered and said to them, “Are you not therefore mistaken, because you do not know the Scriptures nor the power of God? For when they rise from the dead, they neither marry nor are given in marriage, but are like angels in heaven.”

Angels don’t reproduce

Luke 24:39

“Behold My hands and My feet, that it is I Myself. Handle Me and see, for a spirit does not have flesh and bones as you see I have.”

God’s living creations reproduce according to their kind

Genesis 1:24

Then God said, “Let the earth bring forth the living creature according to its kind”

Cited Sources: NKJ by God, equip.org (Article: JAG062 by Thomas A. Howe), The complete bible answer book by Hank Hanegraaff

Can Fallen Angels Mate With Humans? 

Some rationalize it this way: The Bible gives examples where angels were on earth in a human-like form. In Genesis 18-19 we read about angels who looked like men. They even ate and slept. A few chapters later we’re told that 2 angels went to the city of Sodom and the inhabitants simply considered them to be human visitors. Furthermore, if angels couldn’t take the form of man or at least appear like men, how is it that some can “entertain angels unaware” 

Hebrews 13:2

Do not neglect to show hospitality to strangers, for by this some have entertained angels without knowing it.

The Bible classifies some angels as “elect” 

1 Timothy 5:21

I solemnly charge you in the presence of God and of Christ Jesus and of His chosen angels, to maintain these principles without bias, doing nothing in a spirit of partiality.

Holy Angels

Matthew 25:31

Mark 8:38

All angels were  holy, enjoying the fellowship of God

Matthew 18:10

and the environment of heaven

Mark 13:32

But at some point other angels opposed God under the leadership of Satan

Matthew 25:41

2 Peter 2:4

Jude 6

Ephesians 6:12

Dark angels fell to the earth.

The Nephilim being mentioned again after the flood suggests that it’s possible that fallen angels again had children with humans. The Bible tells us that there were only 8 flood survivors (Noah and his family). So if the Nephilim were merely the result of the descendants of Seth and the descendants of Cain having children, all of those people would have been wiped out by the flood. 

Numbers 13:33

Video: Peter Gentry