Yes, this is a common view on Isaiah.  In fact, for the scholarly types, it is the majority view by a wide margin.  The most common view is that there were at least two authors, with the fairly clear division in Isaiah coming at chapter 40.  There is some division between the two-author and three-author camp, with some proposing a 3rd Isaiah starting with Ch 55 or 56.  I believe that this theory is not the result of Marxism!   Marxists generally have no theories about the Bible.  They mostly ignore it.  But it is “liberal” scholars who claim to be Christian who have created this theory, not Marxists.

This theory did not come out of thin air, and we would do well to not simply dismiss it as the result of unbelievers and the enemies of Christianity.  Instead, we should listen to what these folks have to say, and, after listening and considering carefully, but also listening to those who disagree, we need to come to our own conclusion.  The fact is that there is a rather abrupt change of theme and style of writing at Isaiah 40.  Actually, there is a change at Ch 36 as well.  The first 35 chapters are prophecies to Judah and to the surrounding peoples.  Ch 36-39 are historical narrative.  The historical narrative seems to fit in with the context of the first 35 chapters.  It is in Chapter 40 that the fairly dramatic change in context happens.  The first 39 chapters primarily focus in on events that happened during Isaiah’s lifetime, at the end of the  Northern Kingdom and in the first couple of decades after the destruction of Samaria.  Beginning in Ch 40, the subject matter is things related to the captivity of Judah and the restoration of Judah under Cyrus.  If Isaiah has just one author, then this part deals with things in the future for Isaiah.

A couple of things to think about.  Many—in fact a majority—of supposed biblical scholars are not true believers. Let me define what I mean.  The majority of scholars do not accept that the entire Bible is inspired by God.  They see a human rather than a divine source of the Old Testament materials.  The problem for these people is that Isaiah clearly anticipates events which came after the time that the prophet we know of as Isaiah lived.  If one assumes that the Bible is NOT inspired by God, then one must also assume that Isaiah did not write this material.  As Hamlet said, “Aye, there’s the rub.”  This group of scholars knows a priori, that Isaiah 40-55 was not written by the person we know of as Isaiah.  Only a God-inspired author could have produced prophecies such as Isaiah 44-45, which mentions Cyrus the Persian.  Therefore, the majority of scholars are forced to produce a theory which has at least two different authors.  This fact makes me extremely leery to accept their conclusions.  This amounts to circular reasoning.   How do we know that Isaiah 40-55 was not written by Isaiah?  Because we know that it could not have been written by Isaiah.  Any theory derived with this presupposition in my mind is highly suspect.  Circular reasoning is not an argument at all.

Should we, therefore, reject the idea of two or more authors of Isaiah?  I say that we conservative believers should not allow ourselves to be guilty of the same sort of circular presuppositional kind of thinking.  We believe in the inspiration of the Bible, and we certainly believe that God could inspire Isaiah to prophesy events more than one hundred years after he died.  But, we should not simply dismiss this theory.  We should look at the evidence.  By the way, it is worth noting that there is a very clear historical prophecy in Isaiah 39:5-7 which was certainly fulfilled nearly one hundred years after Isaiah died. How do these liberal scholars handle that one, which defies their division at chapter 40?  Good question.   Also, there are a number of messianic prophecies in the earlier parts of Isaiah, such as Isaiah 7:13-17, Isaiah 9:1-7, and, perhaps most notably, Isaiah 11:1-5.  These prophecies do not concern the time of Babylon and Persia, so they do not undermine the DeuteroIsaiah theory, but they do demonstrate that there are inspired predictive prophecies in both parts of Isaiah.

I have looked long and hard at the arguments for the division of Isaiah into at least two authors, with the division at Ch 40.  I note the rather stark break in subject matter and style in this chapter.  Like I already said, this theory did not come out of thin air.  When I listen to those who do not begin with a presupposition based on the assumption that Isaiah is NOT inspired by God, I find myself unsure.  The evidence I have seen tells me that there are quite a bit more similarities between the two sections than there are differences.  I lean slightly toward the conclusion that there is one principal author of the entire book, but I would not bet my life on this conclusion.  What I know for sure is that the entire book of Isaiah is inspired by God, and it contains fantastic faith-building predictive prophecies, not only about the time of the Babylonians and Persians, but also the time of Christ.  The messianic prophecies are many. Isaiah 43:1-4, Isaiah 49:8-12, Isaiah 52:13-53:12, and others.  One thing I can say with great certainty.  These prophecies about Jesus were written before the events were fulfilled!  Therefore, what is the problem with believing that the prophecies about Babylon and Persian were also written before the events?  Even if there is a second author—based on content and style—that author surely lived before the events he prophesied!  It would be inconsistent and illogical to have Isaiah 1-39, with its inspired messianic prophecies, but then Isaiah 40-55 (or 66) with faked prophecies, which are presented as predictions, when in reality, they are fictionalized prophecies.  This liberal-inspired theory has some logical problems!

I would note that there is nothing in the Book of Isaiah itself which makes the claim that all of its content was written by the person we know of as Isaiah.  Chapter one begins with the statement that the prophecy which follows is from Isaiah, son of Amoz.  But we cannot say with absolute certainty that this applies to the entire content of the book.  For this reason, if there were two different authors, or if there was an author Isaiah, and a group of authors who produced the material from Ch 40 onward, this would not be a problem for us who believe in the inspiration of the Bible.  I have rather little skin in the game of defending the singular authorship of Isaiah.  What I will defend vigorously, and because of the evidence, is that Isaiah is in its entirety a Holy-Spirit inspired composition.  And, in the end, this is all that is essential to me.  My lightly-held belief that there is just one author is based on what I hope is an unbiased look at the arguments pro and con.  But this conclusion is held lightly by me.  I am prepared to say that the conservative scholars who agree with the DeuteroIsaiah theory have a point, and holding to this theory does not make one an unbeliever.  Not at all.

I hope this helps.  I prefer to leave people with a definite conclusion, but on the theory of more than one author, I do not have a rock-solid conclusion.  The only thing which is rock solid is that the entire book is inspired by God.

John Oakes