>>82979621
The pushing of Christian frames of interpretation may seem strange, but there's this verse at the end of Genesis 4 (verse 26) Where it uses the phrase
>Call upon the name of the Lord
>And to Seth, to him also there was born a son; and he called his name Enos: then began men to call upon the name of the Lord.
Now this is exciting if you've read the NT before, because one of the most obvious/ significant salvation verses is Romans 10:13
>For whosoever shall call upon the name of the Lord shall be saved.
After Enos is born, people start calling upon the name of the Lord = becoming Christian = Becoming sons of God.
Nephillim are just giants (8 - 12 foot tall people (the bible says how tall a giants bed is at some point, pic rel is google's estimate), but probably functionally giant, not just suffering from gigantism, an example in history would be Angus MacAskill from Canada), so decently tall, but not like jack and the giant beanstalk/ attack on titan size.

Anyway People get saved => Become sons of God => descendants marry the families that aren't Christians (because they have better genes = more attractive) => Offspring are more robust, healthier, taller, etc
>the same became mighty men which were of old, men of renown.
The shift to Genesis 6:5 being God being fed up with humanity, might lead you to think they're connected, but I think they're only chronologically connected, the reasoning of his motivation to flood the earth being given twice as that violence was widespread.