Monotheism among the Christians its concept and Creed implications(Critical Study)

Jesus was mentioned in the Holy Quran as considering God as one, God as his Lord and ordered to worship God only. However, some Christians who believed in Jesus Christ as Prophet and denied him as being Son of God or one of the Three Gods; an evidence of the depravity of the Creed of most Christians and its perversity of Jesus Message, and a reply to the followers of the three large parties (Royalism, Nestorianism and Jacobitism) in Triangulation, and the study of the Christians attitude on Monotheism throughout ages and their switch to Triangulation and notification of the invalidation of their saying of the godhead of Jesus; features the importance of this research [Monotheism among the Christians its concept and Creed implications (Critical Study)]. We will tackle here the concept of Monotheism as seen by Christians, and Monotheism after Jesus, Peace be Upon him, was lifted, the stages of Monotheism in the Christian history and texts of the Holy Book and the proof of Monotheism Creed to the Almighty God and the reply to it.