One of the common ways biblical scholars attempt to uncover the sense of Hebrew words with unknown meanings, or to propose new meanings for well-attested words, is through appeal to cognate languages. Among the languages used for such purposes none has been more frequently cited than Arabic. This dissertation studies the methodology employed by Hebraists drawing upon the Arabic sources, points out some of the flaws occasionally found in their work, and suggests ways of avoiding such pitfalls in the future.