This volume is the earliest dated Judeo-Persian manuscript in The JTS Library collection. It contains three linguistic and philological texts, including Sefer ha-Korhah (Book of the Dissenter). This short but highly influential treatise, written in the late 10th century by Judah ben David Hayyuj, was the first explanation of the Hebrew language’s structure based on a system of three-consonant roots (called a shoresh) and it revolutionized the study of the biblical language. Hayyuj’s analysis became the foundation for all later Hebrew grammar, influencing both Jewish and Christian scholars in the medieval period. The book is open to the first text in the volume—a biblical Hebrew, Aramaic, and Persian dictionary, organized alphabetically by triliteral roots and includes biblical verses in which a word derived from the relevant root appears.