The belief in the Nephilim is rooted in the Hebrew Scripture, in the Book of Genesis. Genesis 6:4: There were giants in the earth in those days; and also after that, when the sons of God came in unto the daughters of men, and they bare children to them, the same became mighty men which were of old, men of renown.
St. Clement of Rome was a disciple of the Apostle St. Peter. He also succeeded Peter as Bishop of Rome (Pope). Clement first century writings record a teaching of the Apostle Peter about these creatures in context of the Fallen Angels. Fr. Jack Ashcraft in his booklet: “Fallen Angels And Nephilim” includes this:
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