the intercourse of the
Jews with the Assyrians in the days of Isaiah." Davidson's Introduction
to the Old Testament, p. 857.

8. It has been shown that the arguments against the genuineness of this
part of Isaiah (and by parity of reason against certain sections of the
first part) have their ground in the denial of prophetic inspiration,
and cannot endure the test of sober criticism. The evidence, then, for
the genuineness of these chapters remains in its full force, and it is
of the most weighty character. If we look to _external_ testimony, there
is the undeniable fact that, as far back as we can trace the history of
the book of Isaiah, they have constituted an integral part of it. They
are recognized as such by Josephus (Antiq. 11. 1, 2); by Jesus the son
of Sirach, in the book called Ecclesiasticus (48:24, 25); and always in
the New Testament when quotations are made from them--Matt. 3:3; 8:17;
12:17-21; Luke 3:4; 4:17-19; John 1:23; 12:38-41, where a quotation from
the _last_ part of Isaiah is joined with one from the _first_ part; Acts
8:28-33; Rom. 10:16, 20, 21. That they were appended by fraud and
forgery no one pretends to affirm. The character of this part of the
book, not less than the character of those who had the Jewish canon in
custody, is a sufficient protection against such a supposition. That
they should have been appended through ignorance is inconceivable. How
can the name of so great a prophet have remained unknown? According to
the hypothesis in question, he lived about the close of the Babylonish
captivity. He was contemporary, therefore, with Daniel; with Zerubbabel
also, Jeshua, and the other chiefs of the restoration. Did no one of
these know who was the man that prophesied so abundantly of the work
which they had so much at heart? And did his name indeed escape the
knowledge of the learned scribe Ezra? And if they did not know his name,
why did they append his writings to those of the true Isaiah, thus
tacitly ascribing to him their authorship? Why did they not leave them
without a name, as they did the books of Judges, Ruth, Samuel, Kings,
and Chronicles? That these chapters have always constituted a part of
the book of Isaiah, and been acknowledged as such, is a fact which
admits of but one explanation; that, namely, of their genuineness. The
_Great Unknown_, as he is called, is no other than Isaiah himself, whom
the principles of certain critics do not allow them to acknowledge as
Isaiah.