Same Spirit?

Musing through Major Themes of the Qur'an by Fazlur Rahman brought up familiar but troubling questions for me.

In describing the themes of the Qu'ran I was struck by how similar they were in their basic content to Judaism and early Christianity. The doctrines of humanity, creation, God's nature, the familiar prophetic pattern of Muhammad's life, and of course the emphasis on monotheism all resonate with the undertones of the previous revelation of Judaism and Christianity.

Assuredly this is not to say that there are not key differences between the three in describing these doctrines and their implications for human life. It is a reflection on the amazing extent to which they are similar. This makes sense in light of the Muslim belief that their religion is just a continuation of the revelation of God communicated through the prophets of old.

A comment Rahman makes on page 96 pinpoints this view saying, "There is no doubt that the agent of Revelation to Muhammad is this Spirit," referring to the Spirit that influenced Abraham, Moses, and Jesus. This seems to make sense and I wish I could embrace Allah being the same God Christians and Jews worship, for certainly he is called by the same name. Unfortunately there are just too many fundamental differences between, for example, the basis of Christianity which is the person of Jesus Christ who is held to be divine and a part of the trinity, and the Muslim view of the prophet (as Rahman points out Muslims reject Jesus' status as God as well as his death and resurrection).

I am left wondering if in fact there was one spirit of God communicating revelation and one of the religions misinterpreted his message. This is what Muslims believe, that Christians and Jews somehow perverted divine revelation.