This dissertation is to collect the Controversial Syntactic Issues of the Arabic Language which are spread all over the explanatory book of the book called "the Neel and Shiffa'a Al-Alil" and study them individually. It also aims to reveal the manifestations of the linguistic thinking with the scientists of the Islamic jurisprudence and its principles; as the subject of the research The above-mentioned author is one of the most famous scholars of the Islamic jurisprudence and its principles. In addition, it aims to highlight the scientific prestige of this above-mentioned book which is one of the largest Jurisprudential encyclopedias written by an Ibadhi scholar. The researcher divided the study to: 1- Preface: Introduction about Sheikh Etfayish and his book. 2. Three Chapters: in the first: the researcher discussed the issues of the grammatical tools, in the second: issues of the nouns, and in the third: other grammatical matters. 3. Conclusion: He mentioned the results of the research and the recommendations. The most prominent results of the study are: 1 - Most of the controversial syntactic issues which are spread all over the explanatory book came as a comment on the words of the original author of the (Neel). 2 - Sheikh Etfayish was brief in his presentations of the controversial issues. 3 - Sheikh Etfayish disagrees with some of the famous opinions adopted by most of the Arabic grammarians. 4 - Sheikh Etfayish tends in his views and terminology to follow the Basri doctrine, but he has taken the views of the Kufi Doctrine in some of the issues.