The nephilim were the offspring of a mortal woman and a
seraph (plural:
seraphim). The angels who came from the
heavens taught man of
magic and
vanity. These angels had off spring with the mortal women known as the Nephilim.
When
God wiped out the
Seraphim and the
Nephilim with a
flood he trapped the Nephilim on earth because they were not completely of the heavens, so they could not enter
heaven. Nor were they completely of the earth, so they could not die.
The Nephilim were the first to be called what is known as
demons or
djinn, forever trapped on earth without
corporeal form. Nephilim inhabited the bodies of mortals in a form of
possession which was believed could be passed by
touch such as with the
major motion picture Fallen. Keep in mind,
biblically speaking, Azazel was actually the leader of the seraphim who came down from heaven to be with man, and
NOT a Nephilim. After the flood, the seraphim were
imprisoned in
hell or
buried alive deep, deep within the
earth where they supposedly still reside.
Throughout the bible, the nephilim are typically refered to as giants (They inherited height from their angel
lineage, but they did not inherit the
wings).
A good reference point for the Seraphim and the Nephilim is the
apocrypha which was once part of the
bible but later removed due to questions over origin. The
Greek Orthodox still retain the apocrypha within their version of the bible.