In varying degrees of intensity and from various angles of concern, defenders of the unity and single authorship of Isaiah contend that to concede the book was formed over a period of time would eliminate the amazingly accurate predictive element of prophecy in the book.
There is sometimes even the claim made that people who suggest anything differently are really trying to promote an agenda that denies belief in prophecy or the trustworthiness of Scripture.
The prophet Isaiah lived in the eighth and early seventh centuries BC.
He was from Jerusalem and began his ministry in 740 BC, the year of King Uzziah’s death.
Cyrus, the Emperor of Persia, lived well over one hundred years later: Cyrus (580-529 BC) was the first Achaemenid Emperor.
Yet The Book of Isaiah in Chapters 44 and 45 speaks of Thus said Jehovah, To His anointed, to Cyrus, Whose right hand I have laid hold on, To subdue nations before him, Yea, loins of kings I loose, To open before him two-leaved doors, Yea, gates are not shut: If this is so, it's a miracle.
The bulk of his ministry took place under Ahaz and Hezekiah.
Note2: In Christian world, this sort of "I told you so" fulfillment lead to disputes of when a text is actually written.
See: Who says Jesus couldnt predict the fall of Jerusalem @Henry - tense has nothing to do with it.
Prophetic visions transcend boundaries of time, space and tense.
CMI is a Christ-centred ministry defending the authority of the Bible right from the beginning.
The Bible written before Christ (the Old Testament) pointed to His First Coming (‘Advent’): God the Creator taking on human nature to die for our sins, then conquer death.