Giants

Giants are real

Are those who believe in the existence of giants idiots?

No this stuff is real and knowledge of it might save your life.

Hosea 4:6 KJV
My people are destroyed for lack of knowledge: because thou hast rejected knowledge, I will also reject thee, that thou shalt be no priest to me: seeing thou hast forgotten the law of thy God, I will also forget thy children.

This notion, that the fallen angels were, in some sense, the fathers of the old giants, was the constant opinion of antiquity

Giants didn't disappear with the flood. Neither are they descendants of Noah's family. No the fallen angels came down on earth after Noah's flood and procreated with the women of men again.

Genesis 6:4 KJV
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.

And they are coming back.

Matthew 24:37 KJV
But as the days of Noe were, so shall also the coming of the Son of man be.

Modern Christianity is all for inclusiveness, tolerance and accept anyone. Let's talk. Let's all get along. Giving reptiles easy access to Christians.

Today's true believer should create underground churches.

The gates of hell are opening.

Jeremiah 30:5-7 KJV
For thus saith the LORD; We have heard a voice of trembling, of fear, and not of peace. [6] Ask ye now, and see whether a man doth travail with child? wherefore do I see every man with his hands on his loins, as a woman in travail, and all faces are turned into paleness? [7] Alas! for that day is great, so that none is like it: it is even the time of Jacob's trouble; but he shall be saved out of it.