Adam Clarke on Revelation 17:5

And upon her forehead was a name written, Mystery, Babylon the Great, the Mother of Harlots, and Abominations of the Earth - This inscription being written upon her forehead is intended to show that she is not ashamed of her doctrines, but publicly professes and glories in them before the nations: she has indeed a whore's forehead, she has refused to be ashamed. The inscription upon her forehead is exactly the portraiture of the Latin Church. This Church is, as Bishop Newton well expresses it, A Mystery of iniquity. This woman is also called Babylon the Great; she is the exact antitype of the ancient Babylon in her idolatry and cruelty, but the ancient city called Babylon is only a drawing of her in miniature. This is indeed Babylon The Great. "She affects the style and title of our Holy Mother, the Church; but she is, in truth, the mother of harlots and abominations of the earth."