Christianity and Islam differ regarding the concept of the Original Sin. According to Christianity, Adam and Eve, the first humans sinned when they ate the forbidden fruit. They were expelled from heaven and sin entered the world. Every child of Adam, you and I, according to Christianity has inherited this sin (as genetic inheritance). Therefore, every male and female is born stained with sin and is therefore destined to hell, from birth. This belief in Christianity gave rise to the doctrine of Atonement. According to this doctrine, God sacrificed his "only begotten" son, Jesus to wash away the sins of the world. The only thing people have to do to wash away their hereditary stain is to believe in Jesus as God's son and that he died for them.
Islam does not agree with all this. According to the Qur'an, every one is responsible for their own doings and nobody can carry the burden of another. God is forgiving and if a person sincerely repents, amends and does what is good and righteous, God forgives. Adam did not ask us before eating the fruit, so how can we be blamed?
In any society, where justice is one of the highest valued morals, killing an innocent man (Jesus) to wash away the sins of the guilty would be condemned as immoral, yet billions of people rejoice over this "gift" of injustice! Once again, the source of conflict is Paul and not Jesus. Jesus never talked about atonement or a "free-ride" through the blood of an innocent man.
On the contrary he said, "…If you would enter life, keep the commandments" (Matthew 19:17). It was Paul who brought the concept of the Original Sin into Christianity.
The Truth About The Original Sin
by: Dr. Abdullah Bin Hadi Al-Qahtani,