Avraham Gileadi argues for the unity of Isaiah.
Avraham Gileadi, The Apocalyptic Book of Isaiah (Provo: Hebraeus Press, 1982), 171
The history of modern scholarship on the Book of Isaiah need not be detailed here. The briefest survey would show that the tendency among scholars to fragment the text has resulted in a serious oversight: failure to consider basic literary structures and patterns that tie together all parts of the book. The very nature of the two chief methods of biblical criticism, the traditio-historical and form-critical approaches, seems to discount a view of the Book of Isaiah as a whole. The book's three distinct historical settings, and its divided content of prophetic oracles and written discourses, are regarded as grounds for the belief that the book has diverse origins: that its sections represent separate entities. Although these two approaches to Isaianic scholarship have brought many valuable things to light, much has nevertheless been overlooked because of their limitations. Only recently have schools of biblical criticism taken seriously the idea of the Book of Isaiah as a literary unity-not as a result of their methods, but as an intuitive reach of what lies beyond their scope. However, in view of evidence of the book's literary unity, a complete rethinking is required to assure this prophetic text not remain, in effect, a sealed book. Without consideration of its literary structure and typology, scholarly attempts at its interpretation must fall short of the mark. On the other hand, when these aspects are considered, the Book of Isaiah unfolds as a coherent and truly prophetic masterpiece of Hebrew literature.