The fundamental difference between Islam and Christianity is then anthropological—or more precisely, hamartiological. Adam did sin, he was indeed punished, but in no way did his guilt develop into what Christians have variously called original sin or original stain. In the Adam narrative [in the Qur’an], as in Gen 3:15 and 3:21, we already have intimations of how this narrative will play out. In the Qur’anic narrative God appears to simply forgive Adam, and then warns him to follow his guidance and not turn from his message. In the Genesis narrative, however, we have hints that God will somehow conquer the serpent through Eve, and furthermore God himself sacrifices an animal to provide garments for Adam and Eve indicating that their garment of fig leaves was not sufficient for covering their nakedness. Both of these would become important images for the early Christians as they struggled towards the formulation of the orthodox tradition. (pp 503, 4)
Miller, Duane Alexander. 2010. ‘Narrative and Metanarrative in Christianity and Islam’ in St Francis Magazine, Vol 6:3, June, pp 501-16.