Claus Westermann was a scholar whose entry into academia was preceded by parish ministry, and his desire to see scholarship's usefulness in its service to a living faith is apparent here, as in his other works. He approaches Isaiah 40-66 from a historical-critical perspective in order to let the beautiful theology of this text ring out, and he does so in a visibly thoughtful manner; his discussion never becomes mired in the overly-technical.
Whether or not one agrees with the validity of a Deutero- and Trito-Isaiah, or with Westermann's identification of who the 'Servant' is, makes little difference to the value of this commentary. The strength of this book lies in Westermann's ability to let the oracles found in Isaiah 40-66 address the concrete issues of their time, the 'situation on the ground', and then, to allow these words to speak powerfully into our present context. It is here that his careful, gentle approach to theology shines, as his scholarly reading of the text helps anchor the meaning embedded in the word.
This is a fine commentary on the second half of Isaiah. He certainly approaches the text with a critical perspective, offering emendations and rearranging sections in a few places, but he returns from it with a sound and studied handling of the word which proclaims comfort (and challenge) to our present faith.