Christianity and Islam are the largest religions in the world. Thirty-three percent of the world’s population are Christian, twenty-one percent Muslim. The world’s two largest religions have much in common, but they are also different in some crucial ways. The origins of both religions are fully described in my book, Science and Technology in World History, Vol. 2.
Both Christianity and Islam are offshoots of Judaism. From Judaism, Christianity and Islam derived the doctrines of monotheism, prophecy, resurrection, and a belief in the existence of heaven and hell.
Both Islam and Christianity have a holy book. Christians consider the Bible the inspired word of God. But Muslims believe that the Koran is the literal word of God. Mohammed was merely transcribing the words of Allah, much as a court reporter does. Muslims therefore attribute greater spiritual authenticity to the Koran and Islam than to the Bible and Christianity.
In Catholicism, salvation is obtained through the sacraments of the Church, including baptism, penance, and the Eucharist. Most Protestant denominations hold the doctrine that salvation depends solely on faith in Jesus Christ. But in Islam, salvation is through works and is not limited to Muslims.
Christianity is focused on forgiveness, charity, and mercy, with a side dressing of apocalyptic visions, Hell, and the wrath of God. But Islam is centered on justice and the destruction of unbelievers. Allah is merciful — but not to infidels. The early history of Christianity is one of persecution and martyrdom. Jesus himself submitted to crucifixion. In contrast, Islam was not born in submission and earnest entreaty, but in warfare against the enemies of Allah.
After the Hegira, Mohammed and his followers began a jihad against their pagan enemies in Mecca. At the Battle of Badr in 624 AD, Mohammed’s servant found one of his master’s enemies lying wounded on the battlefield. He cut off the man’s head and presented it to Mohammed as a present. The Prophet was overjoyed. He exclaimed, “The head of the enemy of Allah! It is more acceptable to me than the choicest camel in all Arabia.” After the bodies of his foes were cast into a pit, Mohammed stood at the edge of the pit and taunted the dead by asking, “Have you found that what Allah threatened is true?”
Consider how Jesus and Mohammed handled what was essentially the same problem. A woman who had committed adultery was brought before Jesus for judgment. As she had been caught in the very act, there was no question of her guilt. The sentence dictated by Mosaic Law was death by stoning, but Jesus showed mercy. He said, “He that is without sin among you, let him first cast a stone at her.” Embarrassed, the woman’s accusers dropped their rocks and walked away. Jesus told the woman to go home and repent. But when a man and a woman who had committed adultery (with each other) were brought before Mohammed, he exclaimed, “Stone them,” and the pair was executed.
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