Ahmad ibn-e Moosa Rashti-e Ostadi is one of the mystic and literary personalities in 9th century A.H He is reckoned as one of the elders that related to Azarbayejan area mysticism. His remaining works consist of Sharh-e Golshan-e Raz, Sharh-e Jam-e Jam (which is belonging to maghreb i), Sharh-e ouhad-al-din kermani's return-tie.His explanation of Golshan-e Raz of Shabestari is one of the most ancient explanations and commentaries of that ethical and mystical verses.Unfortunatly there is not any account in available sources about Ahmad . ibn-e Moosa 's life, works and ideas. For this reson, his personality and his works have not known yet. This essay intends introdus Ahmad ibn-e Moosa briefly, then analys stylistic and cotentual characters of his most important work, Sharh-e Golshan-e Raz, in three levels: literally level, literary level and philosophical level.Jt also evaluates position of that book between Persian mystical prose texts.After analyses that were performed, we can say the results of this research indicate identifiction of writing style, simplicity of sentences and variatioin in meaning expression of Sabestaris verses. Therefore The tradition of writtig commentary on mystic books has been fulfilled by using sign, traditions (Ahadith), mystical, theological, philosophical and astrological terms, so by using Arabic words and by narrating anecdotes and mystics' discourses in style of ancients.