Does Isaiah 40-55 convey a unified message on the relationship between Israel and the nations? This book argues that Isaiah 40-55 contains the texts and concepts of both universalism and particularism. Examining four select texts (42:1-13; 44:24-45:8; 49:22-26; 51:1-8) with special attention given to their textuality, intertextuality, and infratextuality (conceptuality), Hyun Chul Paul Kim suggests the existence of both unified conceptuality and diverse signifiers. Through synchronic and diachronic analyses, this work uncovers the intentional ambiguity, tension, and multiplicity on the concept of the servant's identity as well as other key concepts, how these diverse concepts can be read with respect to authorial intention, and what the implications are for the ongoing debates on the unity and diversity of the book of Isaiah.