Is the Qur'an compatible with Christianity?

I think that Qur'an contains internal contradictions. Also Qur'an and Islam rejects that key figure of Christianity was crucified and it denys His divinity and trinitarian doctrine. Doctrinally they are incompatible, because Qur'an rejects christian trinity and that Jesus( or Isa as they call Him ) was divine, although He is called in Qur'an word of God and some other great titles;

3. Jesus is the Word of Allah.

O People of the Scripture, do not commit excess in your religion or say about Allah except the truth. The Messiah, Jesus, the son of Mary, was but a messenger of Allah and His word which He directed to Mary and a soul [created at a command] from Him. So believe in Allah and His messengers. And do not say, "Three"; desist - it is better for you. Indeed, Allah is but one God. Exalted is He above having a son. To Him belongs whatever is in the heavens and whatever is on the earth. And sufficient is Allah as Disposer of affairs. http://quran.com/4/171

How is the Christian Jesus different from the Muslim Jesus?

The Qur'an Says ...

Holy, Revelation, Mercy When the spirit of Allah appeared as a full-grown man to the Virgin Mary, he announced that she would have a holy son who would be a revelation to mankind and a mercy from Allah (19:17-21).

No Trinity People of the Bible should not exaggerate but speak only the truth about Allah. The Messiah, Jesus son of Mary, was only a messenger of Allah, his word that he gave to Mary and a spirit from him. So believe in Allah and his messengers and stop saying “three.” Allah is only one. He is too transcendent and majestic to have a son. The Messiah is not ashamed to be a slave of Allah (4:171,172).

The Breath and Spirit of Allah Mary, daughter of Imran, who guarded her chastity, is an example of a good wife. Allah breathed into Mary his spirit (the conception of Jesus) and she testified to the truth (that it was a virgin birth) (66:12).

Preached from the Cradle On the Judgment Day, Allah will question Jesus who will be among the other apostles. Allah will ask Jesus if he remembered how he was strengthened by the Holy Spirit and was made to preach to men in his cradle (to defend his mother’s chastity) and as a man (5:110).

Infant Proclamation As an infant Jesus miraculously spoke and proclaimed that he was a “servant” and “prophet” of Allah who had been given the Gospel. The infant Jesus went on to say that Allah had purified him and commanded him to pray, give alms and obey his parents (19:29-33).

Not the Son of God Jesus is the son of Mary. This is the whole truth which Christians are unwilling to believe. It is degrading to think that Allah would have a son! Allah just commands things to happen and they happen (such as Jesus being born of a virgin) (19:34,35). Those who say that Allah has begotten a son proclaim something disastrous. The sky would crack, the earth split apart and the mountains would fall down if they ascribed to Allah a son. It is beneath his majesty (19:88-92). Those who believe Allah had a son are liars who will be punished (10:68,69). Mohammed was told to say that if Allah had a son, Mohammed would be the first to worship him. It is a falsehood that the Christians will have to answer for on the Judgment Day (43:81-83). Allah has no children or wife in his kingdom (25:2).

Only a Slave When the son of Mary is declared as an example (of the Almighty in human form) the idol worshipers ridicule and dispute as to whether their gods are better or Jesus. Jesus is nothing but a slave on whom Allah gave favor and made him an example (of a prophet) for the Children of Israel. Jesus came with clear miracles and told the people to do their duty to Allah and to obey him. He commanded them to worship Allah, their Lord and his (43:57-64).

Strengthened with the Holy Spirit Jesus, son of Mary, was given power to do miracles and strengthened with the Holy Spirit. Yet, when an apostle comes with undesirable teachings, the Jews get prideful and some they call imposters and others they kill (2:87, 253).

No Savior Everyone (including Jesus) will appear before Allah on the Day of Judgment as only a slave who is alone and without a savior or intercessor (19:93-95).

Supported Torah and Predicted Mohammed Jesus, son of Mary, told Israel that he had come to confirm the Jewish Holy Scriptures which came before him, and to announce that another apostle would come after him named Ahmad (61:6).

His Disciples Some Jews followed Jesus as Allah’s helpers and they were blessed to triumph over their enemies (61:14). The disciples of Jesus surrendered themselves to Allah and the Apostle Jesus. They were believers and witnesses. After Allah lifted Jesus up to himself to free Jesus from the unbelievers, the disciples were blessed. The followers of Jesus will be exalted above the unbelievers till the Day of Resurrection when their denominational differences will be settled (3:55).

Worked Miracles Jesus came with clear signs but he was rejected as bewitched (61:6). By Allah’s permission, Jesus brought a clay bird to life, gave the blind sight, healed lepers and raised the dead to life (3:49).

Crucifixion of Christ The Jews have broken the covenant, denied Allah’s revelations and killed the prophets wrongfully. They speak a tremendous slander against Mary. They also say that they killed the Messiah Jesus, son of Mary and Allah’s messenger. They did not kill him or crucify him. It only appeared that way to them. They did not kill him but Allah took him up to himself (4:155-158). After Allah caused Jesus to die (or ascend without dying) and lifted him up to heaven to free Jesus from the unbelievers, the disciples were blessed. The followers of Jesus will be exalted above the unbelievers till the Day of Resurrection when their disputes will be judged (3:55).

Made a Live Bird from Clay On the judgment day, Allah will question Jesus who will be among the other apostles. He will be asked if he remembered how he was given Bible instruction, wisdom and miraculous power. By Allah’s permission, he fashioned a bird from clay and breathed life into it (to make it live) (5:110).

A Table of Food from Heaven On the Judgment Day, Allah will question Jesus who will be among the other apostles. He will ask if he remembered how, by Allah’s permission, he healed the person born blind, cured the leper and raised the dead. The story will be recounted of how Jesus was allowed to call down a table set with food for his followers (5:110-115).

Denies the Trinity On the Judgment Day, Allah will question Jesus who will be among the other apostles. Jesus will be asked if he told mankind to worship him and his mother as two gods besides Allah. Jesus will strongly deny it (5:116-118).

Jesus Is Like Adam Both Jesus and Adam are special creations by the command of Allah (3:59). (This is an interesting verse because the Qur'an rejects the worship of Jesus, yet Satan was banished to hell because he refused to obey Allah’s command to bow before Adam, the man who was sculpted and brought to life from clay. Satan did not believe Allah would ask him to do something so illogical. The story of Satan is found in 7:11-23, 15:28-39, 18:50.) http://answering-islam.org/Authors/Fisher/Topical/ch21.htm

Conclusion Qur'an is not compatible with the doctrines of Christianity concerning trinity, nature of Christ, so Qur'an is not compatible with Christianity.

Short answer.

Islam considers Jesus a prophet just like Moses, Abraham, and Noah.

From Wikipedia:

Muslims deny the Christian doctrine of the Trinity and divinity of Jesus, comparing it to polytheism.

Although Musilms see Jesus as the Messiah, son of Virgin Mary.

(3:45) Surat 'Āli `Imrān (Family of Imran) - سورة آل عمران

[And mention] when the angels said, “O Mary, indeed Allah gives you good tidings of a word from Him, whose name will be the Messiah, Jesus, the son of Mary - distinguished in this world and the Hereafter and among those brought near [to Allah]”.

Conclusion:

Qur’an is +90% the same as the Christian Bible in many aspects, but they cannot be compatible, because Christianity bases its faith and believes in the divinity of Christ, while the Qur'an does not.

You can read similarities and differences in http://www.dianedew.com/islam.htm.

Excerpt Crossing the Threshold of Hope | Pope St. John Paul II [the Great]| Muhammad?

Whoever knows the Old and New Testaments, and then reads the Koran, clearly sees the process by which it completely reduces Divine Revelation. It is impossible not to note the movement away from what God said about Himself, first in the Old Testament through the Prophets, and then finally in the New Testament through His Son. In Islam all the richness of God's self-revelation, which constitutes the heritage of the Old and New Testaments, has definitely been set aside.

Some of the most beautiful names in the human language are given to the God of the Koran, but He is ultimately a God outside of the world, a God who is only Majesty, never Emmanuel, God-with-us. Islam is not a religion of redemption. There is no room for the Cross and the Resurrection. Jesus is mentioned, but only as a prophet who prepares for the last prophet, Muhammad. There is also mention of Mary, His Virgin Mother, but the tragedy of redemption is completely absent. For this reason not only the theology but also the anthropology of Islam is very distant from Christianity.

Conclusion: They are incompatible.

1. Big picture, very few. Small picture, a bit
2. Generally compatible, yes

The problem is "generally" isn't good enough. I'm going to explain in pretty general terms to avoid over complicating this answer, so please don't attack me for not being precise.

Muslims and Christians both originate from Judaism, all believe in God the Father (Christian term). The difference (a major one) is the belief about Jesus. When Jesus came, Christianity split off from Judaism over the belief of whether Jesus was the Son of God or a heretic. The doctrines of the two are pretty compatible since it all has the same origin, but the disagreement about Jesus is enough to start a new religion.

Muslims split off saying Jesus was a prophet/good teacher, but not Son of God. Again, significant disagreement making it incompatible overall. Mohammed also claimed the Bible was inaccurate and retold the stories the way they "actually" happened. After his death, his followers wrote his versions down into what is now known as the Qur'an. Mostly the same stories Christians have, with mostly the same morals, but different details and different belief about Jesus. It also includes things beyond the New Testament era, which are incompatible with Christianity.

Overall, if you are a Christian you should stick with the Bible rather than trying to separate Christian truth and heresy while attempting to learn from the Qur'an

St. Thomas Acquinas (today-28th Jan is his feast day) in his own words gives us a clear contrast as to why one cannot equate Christianity and Islam:

This wonderful conversion of the world to the Christian faith is the clearest witness of the signs given in the past; so that it is not necessary that they should be further repeated, since they appear most clearly in their effect. For it would be truly more wonderful than all signs if the world had been led by simple and humble men to believe such lofty truths, to accomplish such difficult actions, and to have such high hopes. Yet it is also a fact that, even in our own time, God does not cease to work miracles through His saints for the confirmation of the faith.

Thomas points out that given the humble roots of Christianity, it would be more miraculous for the religion to have spread without miracles than with them.  The miracles of Jesus and his apostles provide a reason for the initial spread of Christianity.

Thomas then goes on to differentiate the success of Christianity with the success of Islam.  He argues that Muhammad offered no miracles to prove he was from God, and that his sole appeal was based on the carnal pleasures he offered his followers, including military power. 

Here again is St. Thomas:

On the other hand, those who founded sects committed to erroneous doctrines proceeded in a way that is opposite to this, The point is clear in the case of Muhammad. He seduced the people by promises of carnal pleasure to which the concupiscence of the flesh goads us. His teaching also contained precepts that were in conformity with his promises, and he gave free rein to carnal pleasure. In all this, as is not unexpected, he was obeyed by carnal men. As for proofs of the truth of his doctrine, he brought forward only such as could be grasped by the natural ability of anyone with a very modest wisdom. Indeed, the truths that he taught he mingled with many fables and with doctrines of the greatest falsity. He did not bring forth any signs produced in a supernatural way, which alone fittingly gives witness to divine inspiration; for a visible action that can be only divine reveals an invisibly inspired teacher of truth.

On the contrary, Muhammad said that he was sent in the power of his arms—which are signs not lacking even to robbers and tyrants. What is more, no wise men, men trained in things divine and human, believed in him from the beginning, Those who believed in him were brutal men and desert wanderers, utterly ignorant of all divine teaching, through whose numbers Muhammad forced others to become his followers by the violence of his arms.

Thomas makes some important distinctions between Islam and Christianity based on their respective beginnings.

In case of Islam and Koran, everything that Christianity stands for, is contradicted by Muhammad in Koran. Unlike the content of scriptures of other religions, Koran redefines the events and facts from Bible almost directly on one-to-one basis. Moreover, the reasons for these contradictions are pretty clear.

For Christians, Jesus is the Messiah, the one who by his reconciling death provided atonement for mankind. Koran says Jesus didn't die but was just a prophet and there was no atonement.

About heaven, Muhammad redefined heaven using five passages of the Koran as something like an enormous bordello in the sky.

Heaven is redefined. The work of Jesus on earth is redefined. Even the very nature of God is recast by Muhammad. So whatever Bible teaches as its core message, has already been changed by Muhammad.

There are many verses, to incite Muslims to violence against various kinds of non-Muslims which again directly contradicts message given by Jesus about loving our neighbor to the extent of praying and loving our enemies.

True such verses are found in OT also, but that was a different age and era altogether. In the late Bronze Age, in the time of Moses, Joshua, and right up until King David, human societies apparently had not developed to the point that you could separate a spiritual, religious leadership on one hand from a secular, political leadership on the other. The change was ordained by God in NT, because human societies had developed to a point where the change could be instituted. Yet we see Muhammad has taken it back by several centuries.

When King David said, "I want to build the temple," God said, "No. You will not build my house. You have much blood on your hands. You have fought many wars in my sight. Your son Solomon is a man of peace. He will build my house."

Now the reasons for these contradictions:

It happened because Muhammad had limited knowledge of the Old Testament and even less of the New Testament. But he was pretending that he had complete knowledge. So he kept getting the stories wrong. In the Koran, Muhammad tells the story of Moses' confrontation with Pharaoh, the Exodus story, 27 times in 89 chapters. There's not one mention of the Passover. He told the story of Gideon's, only it wasn't Gideon, it was King Saul.

Koran places the Samaritans at the time of Moses when such people had not existed at that time.

Another contradiction is claiming Mary, mother of Jesus same as Miriam, sister of Aaron and Moses. These two women lived 1500 years apart. The Koran says.

She brought (the babe) to her people, carrying him (in her arms), They said: “O Mary! Truly a strange thing has thou brought! “O sister of Aaron, thy father was not a man of evil, nor your mother a woman unchaste!” Q. 19:27-28

This is repeated in verse 66:12 where Muhammad calls Mary, daughter of `Imran.

Now, it was not until about 200 years after his death that Muslim leaders learned Latin. Some of them learned Greek. They could read the Vulgate Latin Bible or the Greek New Testament, and they began to see that there was a Passover in the Exodus story and thier prophet didn't mention it. So they had to either admit that he was mistaken, he didn't really know what he was talking about, or the option was to blame the Jews for having tampered with the Scriptures, so that God had to use Muhammad to restore the Old Testament to its original form.

I'll start with what Christian views I know the Qur'an explicitly denies.

Trinity

Qur'an 4:171 O People of the Scripture, do not commit excess in your religion or say about Allah except the truth. The Messiah, Jesus, the son of Mary, was but a messenger of Allah and His word which He directed to Mary and a soul [created at a command] from Him. So believe in Allah and His messengers. And do not say, "Three"; desist - it is better for you. Indeed, Allah is but one God. Exalted is He above having a son. To Him belongs whatever is in the heavens and whatever is on the earth. And sufficient is Allah as Disposer of affairs.

Jesus, the son of God

Qur'an 9:30 The Jews say, "Ezra is the son of Allah "; and the Christians say, "The Messiah is the son of Allah ." That is their statement from their mouths; they imitate the saying of those who disbelieved [before them]. May Allah destroy them; how are they deluded?

I can't really say anything about how the Qur'an relates to Christianity other than for these points. Feel free to edit this answer or copy content to your own answer.

Jesus died on a cross

Qur'an 4:157-158: [157] And [for] their saying, "Indeed, we have killed the Messiah, Jesus, the son of Mary, the messenger of Allah ." And they did not kill him, nor did they crucify him; but [another] was made to resemble him to them. And indeed, those who differ over it are in doubt about it. They have no knowledge of it except the following of assumption. And they did not kill him, for certain. [158] Rather, Allah raised him to Himself. And ever is Allah Exalted in Might and Wise.

No, it is not compatible. The Qur'an explicitly denies the divinity of Christ, which is one of the absolute bedrock tenets of the Christian faith. Without His divinity and associated sinlessness Christ's sacrifice and resurrection would carry no meaning or effect.

One additional note: I ran across this article today and I thought it would round out this answer well. In it the author explains the doctrine of the Trinity and why it matters so much. The fact that Christ was divine and one part of a triune Godhead is critical to Christianity, and as I said the Qur'an denies it outright. A great summary of the Trinity from the article:

The doctrine of the Trinity can be summarized in seven statements. (1) There is only one God. (2) The Father is God. (3) The Son is God. (4) The Holy Spirit is God. (5) The Father is not the Son. (6) The Son is the not the Holy Spirit. (7) The Holy Spirit is not the Father. All of the creedal formulations and theological jargon and philosophical apologetics have to do with safeguarding each one of these statements and doing so without denying any of the other six.

Without a Trinity there is no Christianity, therein lies the direct conflict with the Qur'an.