The ܫܚܝܡܐ Shhimo is the prayer book for normal weekdays of the Syrian Orthodox Church and it was officially printed for the first time in Dayro d-Kurkmo (Dayr Al-Zafaran) in 1890 with a printing press that Patriarch Ignatius Peter IV (+ 1894) had received in 1874 thanks to his visit to London and the Anglican Church. Prior to 1890 Shhimo was a diverse tradition expressed with different manuscripts in different monasteries showing a diverse use of different prayers and costumes. The second printing of Shhimo in 1913 and re-printing 1934, by the late Syrian Orthodox Patriarch Ephrem I Barsoum (+ 1957), was a reworked version of 1890 that included several important changes. This thesis will investigate what these changes were and what implications they carry for the understanding of Shhimo and for the Syrian Orthodox Church. In this paper we will also start to investigate the transmission process of the Shhimo and study some of the manuscripts prior to 1890.