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.

Notes:

We are “ON” the earth and not “in” the earth. There is also the problem of the wording “after that” with the Nephilim where it is being used with the serpent seed theory to say that there are still Nephilim running around the world after the flood. I was taught and read where everyone outside of Noah’s family was wiped out. I think there is the possibility of this sort of thing occurring again, but this verse shouldn’t be used for it. I can only think of “there is nothing new under the sun”.