There are some common points that exist between Christianity and Islam. What are the similarities and disagreement between Christianity and Islam?
I read a lot on Islam and Quran, and I think best source to know and understand something is to listen to it directly from its sources. I also read the material like this, which they use to convert people. That way I will know what I accept and what I reject, and if I am with the truth I have nothing to fear. I am writing directly from the Quran here, without any comments, leaving the judgement to you. To start with some verses from the Quran, telling us about a different miracle of Jesus, him talking in the cradle, but maybe not in the way it would fit in the Gospels.
27.Then she brought him to her people, carrying him. They said, "O Mary, you have certainly done a thing unprecedented.
28.O sister of Aaron, your father was not a man of evil, nor was your mother unchaste."
29.So she pointed to him. They said, "How can we speak to one who is in the cradle a child?"
30.[Jesus] said, "Indeed, I am the servant of Allah . He has given me the Scripture and made me a prophet.
31.And He has made me blessed wherever I am and has enjoined upon me prayer and zakah as long as I remain alive
32.And [made me] dutiful to my mother, and He has not made me a wretched tyrant.
33.And peace is on me the day I was born and the day I will die and the day I am raised alive."
34.That is Jesus, the son of Mary - the word of truth about which they are in dispute.
35.It is not [befitting] for Allah to take a son; exalted is He! When He decrees an affair, He only says to it, "Be," and it is.
36.[Jesus said], "And indeed, Allah is my Lord and your Lord, so worship Him. That is a straight path." http://quran.com/19/27-36
Islam claims to be the religion of submission to God only. It is a pure monotheistic faith, with severe criticism about trinity, or any other type of polytheism. In Quran anything similar to polytheism is mentioned with anger and mentions the concept of a son with "being an atrocious thing" which would almost make the universe collapse.
88.And they say, "The Most Merciful has taken [for Himself] a son."
89.You have done an atrocious thing.
90.The heavens almost rupture therefrom and the earth splits open and the mountains collapse in devastation.
91.That they attribute to the Most Merciful a son.
92.And it is not appropriate for the Most Merciful that He should take a son.
93.There is no one in the heavens and earth but that he comes to the Most Merciful as a servant.
94.He has enumerated them and counted them a [full] counting.
95.And all of them are coming to Him on the Day of Resurrection alone.
96.Indeed, those who have believed and done righteous deeds - the Most Merciful will appoint for them affection.
97.So, [O Muhammad], We have only made Qur'an easy in the Arabic language that you may give good tidings thereby to the righteous and warn thereby a hostile people.
98.And how many have We destroyed before them of generations? Do you perceive of them anyone or hear from them a sound? http://quran.com/19/88-98
This is one of the most important chapters for Muslims:
1.. Say, "He is Allah , [who is] One,
2. Allah , the Eternal Refuge.
3. He neither begets nor is born,
4. Nor is there to Him any equivalent." http://quran.com/112
This is designated as the most important verse by the Prophet of Muslims:
Allah - there is no deity except Him, the Ever-Living, the Sustainer of [all] existence. Neither drowsiness overtakes Him nor sleep. To Him belongs whatever is in the heavens and whatever is on the earth. Who is it that can intercede with Him except by His permission? He knows what is [presently] before them and what will be after them, and they encompass not a thing of His knowledge except for what He wills. His throne extends over the heavens and the earth, and their preservation tires Him not. And He is the Most High, the Most Great. http://quran.com/2/255
Following explains the Islamic perspective on Jesus, acknowledging his birth, but claiming he was a human being.
55.[Mention] when Allah said, "O Jesus, indeed I will take you and raise you to Myself and purify you from those who disbelieve and make those who follow you [in submission to Allah alone] superior to those who disbelieve until the Day of Resurrection. Then to Me is your return, and I will judge between you concerning that in which you used to differ.
56.And as for those who disbelieved, I will punish them with a severe punishment in this world and the Hereafter, and they will have no helpers."
57.But as for those who believed and did righteous deeds, He will give them in full their rewards, and Allah does not like the wrongdoers.
58.This is what We recite to you, [O Muhammad], of [Our] verses and the precise [and wise] message.
59.Indeed, the example of Jesus to Allah is like that of Adam. He created Him from dust; then He said to him, "Be," and he was.
60.The truth is from your Lord, so do not be among the doubters.
61.Then whoever argues with you about it after [this] knowledge has come to you - say, "Come, let us call our sons and your sons, our women and your women, ourselves and yourselves, then supplicate earnestly [together] and invoke the curse of Allah upon the liars [among us]."
62.Indeed, this is the true narration. And there is no deity except Allah . And indeed, Allah is the Exalted in Might, the Wise.
63.But if they turn away, then indeed - Allah is Knowing of the corrupters.http://quran.com/3/55-63
Islam defines Christianity, that is being a Christ-follower, to be made up by people and rejects the ideas of Judaism, that concentrate on race. Islam calls followers of this two religion as People of the Scripture. Islam claims, Abraham is distorted by "The People of the Scripture". It claims, Abraham was a monotheist, not having anything to do with a Jewish race - he is the grandfather of Israel (Jacob)- and with a Christ to worship.
64.Say, "O People of the Scripture, come to a word that is equitable between us and you - that we will not worship except Allah and not associate anything with Him and not take one another as lords instead of Allah ." But if they turn away, then say, "Bear witness that we are Muslims [submitting to Him]."
65.O People of the Scripture, why do you argue about Abraham while the Torah and the Gospel were not revealed until after him? Then will you not reason?
66.Here you are - those who have argued about that of which you have [some] knowledge, but why do you argue about that of which you have no knowledge? And Allah knows, while you know not.
67.Abraham was neither a Jew nor a Christian, but he was one inclining toward truth, a Muslim [submitting to Allah ]. And he was not of the polytheists.
68.Indeed, the most worthy of Abraham among the people are those who followed him [in submission to Allah ] and this prophet, and those who believe [in his message]. And Allah is the ally of the believers. http://quran.com/3/64-68
There are many places like this in Quran, calling "The People of Scripture" to monotheism. The Quran claims to be original and not derived from any other book.
101.[He is] Originator of the heavens and the earth. How could He have a son when He does not have a companion and He created all things? And He is, of all things, Knowing.
102.That is Allah , your Lord; there is no deity except Him, the Creator of all things, so worship Him. And He is Disposer of all things.
103.Vision perceives Him not, but He perceives [all] vision; and He is the Subtle, the Acquainted.
104.There has come to you enlightenment from your Lord. So whoever will see does so for [the benefit of] his soul, and whoever is blind [does harm] against it. And [say], "I am not a guardian over you."
105.And thus do We diversify the verses so the disbelievers will say, "You have studied," and so We may make the Qur'an clear for a people who know. http://quran.com/6/101-105
The Quran has some significant differences than Gospels, because it does not tell the story of Muhammad, but talks to Muhammad, mentioning and telling about other prophets. As can be seen here, the name Muhammad is mentioned only 5 times throughout the whole Quran, while Moses 136 and Jesus 25 times by their names. The significant difference is that Quran tells the stories of Biblical prophets with emphasizing them as being innocent and far from having the atrocities attributed to them in the Old Testament. Noah getting drunk, David getting his soldier killed, Solomon worshiping idols, etc. are false and a result of the distortion of the revelations according to Islam.
The stance of Quran on Christianity and Biblical characters can be understood better with the following chapters, some of them with the names of them, actually:
The fundamental claim of Islam is that there is only one God and Mohammad is his prophet. This is believed because it is written in the Qur'an. The Qur'an is believed to be true based on Mohammad's testimony that he received it from the angel Gabriel.
Mohammad claimed to be the last in a long line of prophets, including most of the major Old Testament figures like Adam, Noah, Abraham, Moses, David, Elijah, etc., as well as Jesus. He claimed that the messages God gave to the other prophets were true (and were one with Islam). Muslims have concluded that the real Jesus and his message have since been lost or corrupted and what we now know to be Christianity is not reliable (because it disagrees with the Qur'an). Islam asserts that it is in accord with the real teachings of the prophet Jesus (which we no longer have in a reliable form). The Qur'an asserts that Jesus was not divine and never died (and, by implication, did not come back to life).
If you don't wholly accept its claim that Islam has been around since the first prophet, Adam, then Islam is post-Christian. Mohammad appears to have known a little about Christianity (and perhaps Judaism). What he wrote down shows some familiarity with Christianity but also a severe misunderstanding of it and complete ignorance of some historical details (e.g. placing Samaritans with Moses).
Its relationship to Christianity is that it attempts to supersede Christianity by incorporating selected elements of Judao-Christian beliefs while simultaneously denying the fundamental beliefs both of Judaism and Christianity. Islam is logically incompatible with both Christianity and Judaism as we understand them. Judaism points to Jesus. Nothing in Christianity points to Mohammad. The movement started by Mohammad is superficially rooted in Judao-Christian history, but differs in important facts all along the way. As a movement, it is completely distinct and separate from Christianity, and its fundamental beliefs are mutually exclusive with those of Judaism or Christianity.