Leviticus 18:28 (Artscroll English Tanach):
"Let not the land disgorge you for having contaminated it, as it disgorged the nation that was before you"
The commentary for this verse says:
"The land's holiness cannot tolerate the sort of sins described in this chapter, and it was about to vomit out its Canaanite inhabitants because they persisted in these activities. When the Jews themselves began to indulge in such behavior, they too, were disgorged."
From this passage and this commentary I understand that this land was (and still of course) already Holy before the Israelites entered it, and among all the pagan nations, the inhabitants of this land were the most severely punished due to their idolatry and driven out of this land.
Why this land is holy ? Why G-d choose this land for Israelites and not any other land ?
P.S: I know because of the promise to Abraham, but my point is why this land specifically ?
1- The climate requires rain, and thus prayer, rather than reliance on a body of water.
2- Ideas discussed in the location where the three continents where the bulk of humanity lived will spread the fastest.
3- Adam was made on the Temple mount. (And one needn't be a literalist about Creation to believe that the first homo sap, the "clay", in whom a self-aware soul woke up was in Israel.)
– Micha Berger Dec 09 '15 at 17:26