I think that the depiction of Jesus in the Quran, that of a human prophet, is likely to be closer to Jesus’s own self-conception than the divine saviour notion which became established within Gentile Christianity after his death.
While it may seem strange at first blush, since Islam is a much younger religion than Christianity, I have come to think this way through looking into the Ebionites, an early Jewish Christian group, whose theology is thought to have had some influence on Islam.
The old Catholic Encyclopedia entry on the Ebionites begins :
By this name were designated one or more early Christian sects infected with Judaistic error.
The encyclopaedia entry continues:
Recent scholars have plausibly maintained that the term did not originally designate any heretical sect, but merely the orthodox Jewish Christians of Palestine who continued to observe the Mosaic Law. These, ceasing to be in touch with the bulk of the Christian world, would gradually have drifted away from the standard of orthodoxy and become formal heretics.
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Some Ebionites accept, but others reject, the virginal birth of Christ, though all reject His pre-existence and His Divinity.
The crux of the matter is, then, who actually drifted? Who were the heretics and who were the orthodox followers?
It seems to me far more likely that the Ebionites, who traced their lineage back to James and the Jerusalem Church, and who did not move away from the sociocultural influences of the Middle East, stayed true to the way Jesus was seen by his original Jewish followers. In other words, the Ebionites didn’t drift, they didn’t mysteriously demote Jesus, rather the gentile Christians promoted him to divine status. The notion of a God-man arose in the Pauline branch of Christianity but would have been anathema to his earliest Jewish followers and their descendants, who saw him as a cherished, charismatic prophet, just like Muslims do.
The connection between Ebionite theology and Islam has been noted by a number of scholars.
Muhammad was influenced by his first wife Khadijah’s cousin who was said to have been an Ebionite priest, the Ebionites having gone into exile after the fall of Jerusalem and having some sort of presence in Arabia hundreds of years later, still carrying a torch for Jesus.