The holiness of Jerusalem

Question

Why is Jerusalem holy to the Jews? Can you justify this by Torah or Tanakh relevant verses?

Answer 1

Wikipedia answers your question

Jerusalem appears in the Hebrew Bible 669 times [...] For example, the book of Psalms, which has been frequently recited and memorized by Jews for centuries, says:

• "O God, the nations have entered into your inheritance, they have defiled the sanctuary of your holiness, they have turned Jerusalem into heaps of rubble...they have shed their blood like water round Jerusalem..." (Psalms 79:1–3);
• "...O Jerusalem, the built up Jerusalem is like a city that is united together...Pray for the peace of Jerusalem..." (Psalms 122:2–6);
• "Jerusalem is surrounded by mountains as God surrounds his people forever" (Psalms 125:3);
• "The builder of Jerusalem is God, the outcast of Israel he will gather in...Praise God O Jerusalem, laud your God O Zion." (Psalms 147:2–12)

ohr.edu explains why the name Jerusalem itself doesn't appear directly in the Torah

Jerusalem is mentioned many hundreds of times in the Jewish Bible. [It doesn't appear in the Chumash (Five Books of Moses)] [...] because it was not yet called Jerusalem.

Under Jebusite rule and earlier, Jerusalem was divided into two cities, the western part called Jeru (Yere) and the eastern part called Salem (Shalem). Both of these names do appear in the Five Books: "And Malki-Tzedek, King of Shalem" (Genesis 14:18). "And Abraham called that place...Yere" (Genesis 21:14).

Around the time of Joshua's conquest, the Amorites consolidated the two halves of the city, and they combined the two names: Jeru-salem. From this point on in history, our Bible refers to Jerusalem countless times.

Furthermore, the Chumash refers 19 times to "the place that G-d will choose" as the center for Jewish life and religion (e.g. Deuteronomy 12:11, 14, etc.) The Prophets Shmuel and Gad finally reveal to King David that this chosen place is Jerusalem and the Temple Mount.

For further reading see also here and there.

Answer 2

1. In Judaism, holiness does not refer to spirituality but to specialty, Jerusalem is [somehow] different, it stands out, it allows certain things and prohibits others.

2. Our sages summarise it in the Mishna (Kelim 1):

"עֶשֶׂר קְדֻשּׁוֹת הֵן, אֶרֶץ יִשְׂרָאֵל מְקֻדֶּשֶׁת מִכָּל הָאֲרָצוֹת."

"There are ten degrees of holiness. The land of Israel is holier than any other land. Wherein lies its holiness? In that from it are brought the omer [barley offering brought on the second day of Passover], the first fruits, and the two loaves [offered on Shavuot], which may not be brought from any other land.
The walled cities are still more holy, in that they must send forth the metzoraim from their midst, and they may carry around a corpse therein as far as necessary, but once it is taken out, they may not bring it back.
Inside the wall of Jerusalem is more holy than these, because there the less holy [offerings] and the second tithe are eaten. The Temple Mount has greater sanctity, because men and women with discharges, menstruating women, and women who have given birth may not enter there. etc.