Responsa do Królów II 19:34

Answer: Residing in the Land of Israel is a great mitzvah; the Ramban already listed it among the 613 mitzvot, and in the Sifrei (Devarim 80:5) our sages said settling the Land of Israel is equivalent to all of the commandments, as is written, “… and you shall possess it (the Land), and dwell in it. And you shall observe to do all the statutes and judgments which I set before you this day (Devarim 11:31-32). And our sages (Ketubot 110b) already emphasized this by saying, “Anyone who resides in the Land of Israel is like one who has a Lord, as it is written, ‘I am G-d your Lord, who brought you out of the land of Egypt, to give you the land of Canaan, and to be your Lord’ (Leviticus 25:28).” And (Ketubot 111a): “Anyone who resides in the Land of Israel dwells without transgression, as it is stated: ‘And the inhabitant shall not say: I am sick; the people that dwell there shall be forgiven their iniquity.’ (Isaiah 33:24).” And (Ketubot 111a): Anyone who is buried in the Land of Israel is considered as though he is buried beneath the altar. It is stated here: “An altar of earth [adama] you shall make for Me” (Exodus 20:21), and it is stated there: “For He does avenge the blood of His servants, and renders vengeance to His adversaries, and atones for the land of [admato] His people” (Deuteronomy 32:43). And the sages of Israel (Ketubot 112a) would endanger themselves by crossing rivers in order to enter the Land of Israel saying, “This is a place where Moses and Aaron did not merit entering; who says that I will merit seeing this land?” And they would kiss the rocks of the Land of Israel and roll in its dust, as it is written, “For Your servants take pleasure in her stones, and love her dust.” (Psalms 102:15) And (Ketubot 111b) it is called “beauty in the Land of of the Living” (Ezekiel 26:20) - those who are buried there will not suffer the pain of “rolling tunnels,” but the righteous ones who are buried outside the Land do have this suffering, for the Creator makes them tunnels in the ground and (at the revival of the dead) they will roll from there to the Land of Israel and arise, as it is said, “may they blossom out of the city like the grass of the earth” (Psalms 72:16), and “city” means nothing other than Jerusalem, as it is stated: “For I will defend this city” (II Kings 19:34). And it is not permitted to leave the Land of Israel except to study Torah if one cannot find a teacher (in the Land), or to honor parents.