Assalamualaikum.
According to the the Quran every Prophet was a Muslim (Muslim=One who submits his will to Almighty God). And every Prophet that came onto Earth preached a similar message of Islamic Monotheism. Hence we Muslims believe that Islam was since the time when Adam (pbuh) came down to Earth.
Now coming to Jesus Christ (pbuh),
I) Position of Jesus (pbuh) in Islam:
(i)Islam is the only non-Christian faith, which makes it an article of faith to believe in Jesus (pbuh). No Muslim is a Muslim if he does not believe in Jesus (pbuh).
(ii) We believe that he was one of the mightiest Messengers of Allah (swt).
(iii) We believe that he was born miraculously, without any male intervention, which many modern day Christians do not believe.
(iv) We believe he was the Messiah translated Christ (pbuh).
(v) We believe that he gave life to the dead with God’s permission.
(iv) We believe that he healed those born blind, and the lepers with God’s permission.
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