Jeremiah 51:53 - Ellicott's Commentary On The Whole Bible

Though Babylon should mount up to heaven... — The special form of the phrase recalls the language of the builders of the Tower which made the name of Babylon conspicuous (Genesis 11:4). Even though that boastful attempt should be realised, Jeremiah says, it should prove a vain defence. As it was, the walls of Babylon which Nebuchadnezzar had built were of enormous height. Greek writers, possibly speaking of different walls (as there were two lines of fortifications), give from 75 to 335 feet. Nebuchadnezzar, in one of his inscriptions, records their greatness in words that remind us of Daniel 4:30. “To make more difficult the attack of an enemy against Imgur Bel, the indestructible wall of Babylon, I constructed a bulwark like a mountain” (Oppert, Expéd. en Mésop., i. p. 230; Records of the Past, v. p. 131).