Only recently have I heard this theory about Noah and his family being “Perfect in His Generations” as meaning he was totally human and not part Nephilim. Where do you get that? Does the definition of the original words in the original Hebrew imply genetic purity or does it mean simply, “one who walks with God?”
Genesis 6:9 states, “Noah was a righteous man, blameless among the people of his time, and he walked with God.” This seems to be the context of him being “perfect” in his generation because the verse is speaking of behavior and a spiritual condition, not a genetic condition. I can’t see how the Nephilim fits in the text of what the passage is talking about. It seems to me that just because verses 1-4 in Genesis 6 introduce the Nephilim, it doesn’t mean the rest of the passage is talking about genetic impurity. This gives an “excuse” for man’s sin as being because they had “demon” blood in them and not because we’re sons of Adam – born with a sin nature.
In the King James, Genesis 6:9 reads.
These [are] the generations of Noah: Noah was a just man [and] perfect in his generations, [and] Noah walked with God.
It contains 4 distinct thoughts. The first one introduces the Book of Noah, one of 10 patriarchal books that make up Genesis. “These [are] the generations of Noah:” The word for generations here really means descendants.
The second is a statement of Noah’s spiritual condition. “Noah was a just man.” It means God considered him to be righteous.
The third concerns his genealogy. “Perfect in his generations.” The Hebrew word for generations here is different from the one in the first phrase. Out of 167 appearances, it’s translated generations in 133 of them, and is never used like the NIV translation that you’ve cited shows. It literally means generations. The word translated perfect means “without blemish.” There was no defect in his genealogy.
And the fourth concerns his relationship with God. “Noah walked with God.” They were in fellowship.
There’s plenty in Genesis 6-7 to condemn mankind. After all the Nephilim couldn’t have taken over the world without man’s help, and the Lord did say that every inclination of their heart was evil. (Gen. 6:5).
But man has been in similar spiritual condition for all of his existence. Something extraordinary happened to cause the Lord to destroy nearly every man and animal in the flood, and that something was Satan’s contamination of the gene pool. According to God’s law the Kinsman Redeemer had to be a man. He couldn’t be an angel or any kind of a hybrid. Noah carried the uncontaminated human gene across the flood and made it possible for Jesus to be born.