The lower part, which was created first, consisted originally of a single earth which God then split into seven. The seven earths are arranged one above another like a stack of plates; we inhabit the top one, and the devil the bottom one, which is hell. Above the earths God placed an analogous stack of heavens; the lowest heaven is our own sky, the topmost is Paradise. The scale is generous by terrestrial standards: the standard distance, that between any two neighbouring plates, takes five hundred years to traverse, and larger dimensions are encountered at the top and bottom (Cook, 26)."
Jacob Neusner, Bruce Chilton, and William Graham (2002) put the notion of Christian heaven into context by citing 1 Corinthians 15:45-49, which reads:
So also it is written, "The first man, Adam, became a living psyche; the last Adam is life-giving spirit. The spiritual is not first, but the psychic is, then the spiritual. The first man was from Earth - dust. The second man from Heaven. As is the man of dust, such are those who are of dust; as is the heavenly man, such are those who are heavenly (Neusner, Chilton, and Graham, 2002, 46)."
Both Christianity and Islam have punishments that will be dealt to the wicked. The wicked, those who do not have faith, who have done evil deeds, might not see heaven, or at least not in the same way as the devout will see it.
That Muslim phrase echoes the cry of the Biblical prophet that God has humbled Himself to behold the things that are in heaven and earth. Such close affinities of thought, language and religious posture, though never far from radical divergencies, are too wide and real to be disregarded. They mean a significant agreement about man's status before God (Cragg, 1959, 75)."
So we see the many similarities and differences between Islam and Christianity. Just as Christianity followed Judaism, so did Islam follow Christianity, and it was necessary for a couple of things to happen. First, that it closely resembled Christianity enough as to suggest that the idea of a passing of the flame, so to speak, from Christianity was plausible. Therefore we have similarities in the life and experiences of Jesus and Muhammad. We especially find resemblances in those experiences that suggest a relationship with God.
For people who believe that Islam is the third installment of the Word of God, and who wish to convert, the resemblances between Jesus and Muhammad are comforting to that end. For most Christians, however, the vast differences between Jesus and Muhammad are enough to convince them that they belong in the fold of Christianity. There are people who would point out that Jesus was a teacher of peace, and that Muhammad experienced no conflict in killing a person to defend his faith. Although while in Mecca, Muhammad had confined his work to calling the faithful to Allah, he was later forced to defend Islam against the non-believers (Cook, 53-54). Jesus, on the other hand, would lay down his life, turn the other cheek, and would not respond to threats with violence, and he did not encourage his disciples to respond that way either. Jesus was confident that the unbelieving would be dealt with. In fact, we have the Book of Revelations that talks about how the unbelieving, the evil, and sin in general would be counted against mankind and how that punishment would be meted out at the hand of God in the most horrific of ways (Bible, New Testament, Revelations).
For Christians as for Muslims, as taught by both Jesus and Muhammad, life is about preparing for that which will come to us as the faithful - or, unfaithful.
For Islam as for Christianity this life is a preparation for what is to come, but no one will seriously prepare himself for something that appears to him unreal, a fantasy, a dream. It is difficult enough for the young to grasp in an entirely concrete manner the fact that -- assuming they survive -- they will eventually be old people. How much more difficult, then, for the human creature, young or old, to understand that divine Judgement, heaven and hell will come as surely as tomorrow's dawn, or yet more surely, since that dawn cannot come unless God so wills, whereas the advent of physical death and all that follows upon it represents the only infallible prediction we can make concerning our own future (Eaton, Gai, 1985, 223)."
There is so much about the lives of Jesus and Muhammad and the destiny of mankind that is shared between Christians and Muslims. There are, however, vast valleys that continue to separate the two traditions as each struggles with their place in the world, and especially a world where the Muslim fundamentalists are exacting their right and opportunity to eliminate the disbelievers, the infidels - and that includes Christians whom by their very existence pose a threat by way of their different and, some might say, competing beliefs.
Cragg, Kenneth. Sandals at the Mosque: Christian Presence amid Islam. New York: Oxford University Press, 1959. Questia. 24 Nov. 2008 http://www.questia.com/PM.qst?a=o&d=9518917.
Eaton, Gai. Islam and the Destiny of Man. Albany, NY: State University of New York Press, 1985. Questia. 24 Nov. 2008 http://www.questia.com/PM.qst?a=o&d=23211610.
Freedman, David Noel, and Michael J. McClymond, eds. The Rivers of Paradise: Moses, Buddha, Confucius, Jesus, and Muhammad as Religious Founders / . Grand Rapids, MI: Eerdmans, 2001. Questia. 24 Nov. 2008 http://www.questia.com/PM.qst?a=o&d=102109076.
Neusner, Jacob, Bruce Chilton, and William Graham. Three Faiths, One God: The Formative Faith and Practice of Judaism, Christianity, and Islam. Boston: Brill, 2002. Questia. 24 Nov. 2008 http://www.questia.com/PM.qst?a=o&d=113565307.