TheLady and narzos have quite thoroughly established that Jerusalem is definitely considered holy in Islam, but it might still be worth pointing out why this is so.

First and foremost, while the Qur'an is the supreme Islamic holy book, it is not the only one: the Torah and the New Testament are also holy, and so are the prophets described therein. Thus, if Jerusalem is holy to a Jew or a Christian, it is also holy to a Muslim. (This is a bit of an oversimplification since the Qur'an overrides previous texts on a few key issues like Christ's divinity, but this is the "default" setting, so to speak.)

Now, you will recall that Abraham offered to sacrifice Isaac (or Ishmael) on Mt. Moriah, and by tradition Solomon's Temple -- and hence the present day Haram al-Sharif -- was built on this spot. This story is even explicitly retold in Sura 37:102 of the Qur'an. The location of the sacrifice is not mentioned, and some Islamic scholars think it was in Saudi Arabia, but by most traditions the spot was in Jerusalem. (And for what it's worth, neither the Torah nor the Bible specify the location well enough to make a call on this.)

Second, while the Qur'an does not mention Jerusalem by that name (which is not particularly surprising since Yerushalayim is Hebrew), Sura 17 -- which also contains the famous verse cited above -- says quite a bit more about a familiar-sounding place. The land was given to the Children of Israel by Moses (17:2), the Scripture warns that it will be destroyed twice (17:4), and so it was (17:5, 17:7). It being fairly well established that the Promised Land is Israel, it doesn't take too great a leap of faith to connect these two "destructions" to the razings of Jerusalem by the Babylonians and the Romans.

Additionally, in the Hadith Muhammed often refers to Bayt al-Maqdis ("The Purest House") as the destination of his Night Journey:

Abu Hurairah, may Allah be pleased with him, reported:

Allah's Messenger (may peace be upon him) said: I found myself in Hijr and the Quraish were asking me about my Night Journey. I was asked about things pertaining to Bayt Al-Maqdis which I could not preserve (in my mind). I was very much vexed, so vexed as I had never been before. Then Allah raised it (Bayt Al-Maqdis) before my eyes. I looked towards it, and I gave them the information about whatever they questioned me.

Again, some scholars think that the Bayt is only an abstraction of a perfect city, not a physical place. What is certain is that the label is often used for Jerusalem, even among Arabic-speaking Christians and Jews, and has been used as such by people like Saladin and Omar ibn al-Khattab, two of its many conquerors.

Third, since the Holy Mosque of 17:1 is unanimously agreed to be the mosque of Mecca, it would seem rather odd to label Medina the "farthest" place of worship -- the two are only some 250 miles apart from each other, not all that great a distance on the Arabian scale of things as a camel can travel that far in less than two weeks. Remember, Muhammad himself had traveled as far as Syria, well over one thousand miles away.

Now, none of this constitutes ironclad "proof" of Jerusalem's holiness, but as TheLady wisely pointed out Judaism and Christianity can't "prove" holiness either. But the reasons outlined above have been meaningful enough to make Jerusalem the third most holy city in Islam, and dissenters from any are a minority view.


The Holy Qur'an