Throughout his life Robert Browning was fascinated by the idea of language with supernatural power. Powerful, magical language appears in many of his poems and plays, as a model for perfect poetic language. This fascination manifests itself in his life-long interest in magicians and the language of magic, and in Hebrew, traditionally considered the original language, endowed with God's power. Supernatural language is characterised by an inherent connection between signified and signifier that is part of a divine scheme. It does not merely denote; it has an unexplainable and miraculous effect over people and objects in the world. I will explore three kinds of supernatural language in Browning's works; magic language, Hebrew as the original language, and the Word of God. Browning finds such language alluring, in spite of his rational objections to the ideas behind it. In the background there is the developing science of language and theories of supernatural language are being superseded by scientific descriptions of language as an arbitrary system of signs. The eighteenth and nineteenth century debate on the nature and the origin of language is reflected in Browning's works, and Browning's knowledge of this debate and his views on this issue are discussed in the introduction to my thesis. The first and second chapters are concerned with Browning's interest in magic language, and how it is related to his ideas on poetic language. The third and fourth chapters examine Browning's references to Hebrew and to the idea of the ineffable name. The sixth chapter explores the issue of the rift between the Word of God and the human word, and the seventh chapter delineates Browning's construction of the language of the Other: the primitive, the Arab, and the Jew.