The 'Way of the LORD' in the Book of Isaiah

What is the "way of the LORD" in the book of Isaiah? Many scholars have adopted Walter Zimmerli's proposal that the "way" in Second Isaiah is a literal and physical highway extending from Babylon to Jerusalem only to be reinterpreted as a spiritual, metaphorical, and pious way of living in Third Isaiah. This book will properly define each mention of the "way" in Isaiah as well as provide a coherent interpretation of this theme's theological significance within the book. The way of the LORD is initially conceived of in the 1st half of the book as a highway leading to Zion common to both the dispersed Israelites as well as the nations. In Isaiah, Chs 34-35 provide a paradigm of what this way will entail and its theological significance.