Thank you for the question on existence of giants in the land after the Flood, “If Noah and his family were the only people to have survived the worldwide flood, how did giants come to dwell in the land of Canaan when God commanded the Israelites to destroy them?”
Noah and his three children and wives were the only surviving humans after the Flood. Noah and his three sons are direct descendants of Adam and Eve: Shem, Ham, and Japtheh (Gen. 5:32) and their respective wives.
Can it be that the genetic genes carried by Noah and his wife, Shem, Ham and Japtheth with their wives carried a “recessive” gene of giants (Nephilim) or some form of mutation after the Flood? This seems to be the most likely rise of “giants” from the descendants of Noah and his three sons.
Genesis 6 states that there was a co-mingling of the two lines that produced Nephilim. It is possible that one of Noah’s sons married a daughter of a Nephilim and through their childbearing produced Nephilims. This seems to be the most reasonable explanation for giants or Nephilims on earth.
SUMMARY: It is likely that either Noah or his children with their respective wives carried a gene of the Nephilims.
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