This work deals with anthropomorphism and interpretation of the Qu'ran in the theology of the Zaidite imam al-Qasim ibn Ibrahim (785-860 AD). The edition and annotated translation of al-Qasim's epistle, "Kitab al-Mustarshid", is preceded by an introduction which examines early Islamic theology. For the abrogation of the literal meanings of Qur'anic anthropomorphic expressions, the author uses similies, idioms and phrases in Arabic, pieces of evidence from ancient Arabic poetry and rational arguments which often reflect the Mu`tazilite ways of dealing with anthropomorphism. The second subject, the place of the Qur'an in al-Qasim's writings and his methods of interpretation of the Qur'an, bears directly upon his doctrines in general and upon his doctrine of anti-anthropomorphism in particular, and also contributes to the understanding of the development of Qur'anic exegesis in the first half of the 9th century.