"And I will dwell among Bnei Yisroel" (Shemos 30, 45). The Mishkan was built so that Hashem would have an abode wherein He could "reside" down here on Earth. However, one might wonder, "The Torah tells us that His glory fills the entire world. If so, what was unique about the Mishkan that it was described as Hashem's place of residence on Earth. Isn't Hashem found everywhere?"
Rav Wolbe (Alei Shur vol. II pg. 52) cites the Ibn Ezra (Devarim 31, 16) who sheds light on this question. The Ibn Ezra writes, "We know that Hashem is one; the discrepancies come as a result of the perception [of Hashem's hashpa'ah]. Hashem does not alter His deeds for they are all executed with wisdom. An [important] facet of avodas Hashem is ensuring that the recipient reacts in accordance with his location."
Hashem's glory fills the entire world, yet we know that there are ten different levels of holiness in the land of Israel. Additionally, the levels of holiness in the rest of the world cannot compare to the holiness of Eretz Yisroel, for as we know, prophecy could not be received outside of Eretz Yisroel. The Ibn Ezra enlightens us that the difference in holiness is not a difference in Hashem's presence; rather, the difference is in how much His presence is felt. In some locations on Earth His presence is more manifest while in others it is more hidden. Just as certain types of earth are more conducive to planting specific vegetation than others, so too, certain places on Earth are more conducive to feeling Hashem's presence than others.
This idea is essential for those who have moved from chutz la'aretz to Eretz Yisroel. One must recognize that the spiritual climate is not the same in both places and therefore one must adjust his lifestyle accordingly. However, even those who have not made such a move must bear this idea in mind. One who lives in Eretz Yisroel and wishes to daven at the Kosel must prepare himself so that he can gain from the occasion.
When a person goes to hear a shiur or enters a shul or yeshiva, he should be cognizant that he has entered a place that contains a high level of spirituality which is conducive to feeling Hashem's presence. However, if he does not prepare himself accordingly, he will have difficulty gaining from the experience. If he wishes to stay connected to his i-phone while entering a mikdash me'at, he might find himself leaving with no more kedusha than when he entered! A small amount of preparation will allow us to make the most of every spiritual opportunity.