In ancient times false gods were worshiped by men. These "gods" are actually devils (fallen angels). Today they are believed to be aliens.

"For the mystery of iniquity doth already work: only he who now letteth will let, until he be taken out of the way. And then shall that Wicked be revealed, whom the Lord shall consume with the spirit of his mouth, and shall destroy with the brightness of his coming: Even him, whose coming is after the working of Satan with all power and signs and lying wonders, And wit