The faulty notion that the book of Isaiah had multiple authors over centuries (rather than a single author ~700 BC) was first shoveled into Biblical thought by Abraham Ibn Ezra in 1145 AD. Before that, everyone (including numerous people in the New Testament, such as Jesus, John, and Paul) attributed the book to a single author named Isaiah, the son of Amoz, who lived under the Assyrian exile of the northern kingdom of Israel.
Isaiah correctly prophesied that King Cyrus would free Hebrews in a later [Babylonian] exile and the 1st Temple, which was standing during Isaiah’s time, would be rebuilt under Cyrus. The Babylonian exile of the Hebrews started ~605 BC under Nebuchadnezzar. who also destroyed the 1st Jewish Temple in 586 BC.
In 539 BC, the Babylonian kingdom was replaced by the Medo-Persian kingdom. Soon afterward, King Cyrus permitted the Jews to return to their land to rebuild their Temple, which the Jews completed in 516 BC.
Abraham Ibn Ezra couldn’t come to grips with Isaiah’s prophetic words (and their divine implications) so he mused that books 40-66 of Isaiah, which contained the prophecies, were written much later – during the Babylonian exile of the 6th century BC.
Around the 19th century, German scholars succumbed to the same presuppositions of Abraham Ibn Ezra, realizing the divine implications of fulfilled Biblical prophecies. So they frantically assembled tall tales to refute those prophecies by claiming they were written at the same times the prophecies were fulfilled rather than much earlier by other authors than those to whom the books were originally attributed. See other examples from their musings on Moses’ books and the book of Daniel. In the name of high scholarship, academics dug up Abraham Ibn Ezra’s soiled diapers and presented Deutero Isaiah as “scholarship.” Today, their ideas are all the rage, so scholars trying to publish works in refutation are up against an atheistic brick wall.
We’ll be combing through this tangled web of bad ideas in coming weeks. If you’d like to join us, let drop me a reply. I’m looking for experts and have found a few already, thankfully.
SJ Thomason is a business professor who teaches students about leading and managing people in a U.S. university. She’s also a Christian who’s interested in sharing the Good News and Truth of Jesus Christ with others. Visit her on YouTube: https://www.youtube.com/c/ChristianApologist/about