Pe’at HaShulchan, Laws of the land of Israel (Eretz Yisrael) is based on the Vilna Gaon’s halachic system and view on Seder Zeraim and was written by Rabbi Yisrael of Shklov, disciple of the Vilna Gaon in Jewish year 5596. Rabbi Yisrael of Shklov was the leader of Tzfat (Safed) faction of the students of the Vilna Gaon. His community endured attacks from both the Arab and Druze populations, a devastating earthquake, poverty, and various plagues. Most of his close family was wiped out by plagues. He himself became very sick, and as he lay ill and dying with his young daughter Sheindal in his arms, he prayed fervently; learning from the precedent of Yaakov Avinu, he also made a vow to do something special for Hashem if he would survive from this danger. His vow involved writing a major halachic work expounding the laws of the Torah pertaining to living in the Land of Israel. He felt his prayers were answered and fulfilled his vow.
Laws of the Land of Israel (Eretz Yisrael) 1:1
Our Sages stated: “All that dwell in the land of Israel his iniquities are forgiven, for it was stated: “And the inhabitants shall not say, I am sick: the people that dwell therein shall be forgiven iniquity” (Yishayahu / Isaiah 33:24)”. Even if one walked within it 4 cubits one merits the world to come and all that are buried in it gain for themselves atonement and it is as if the place that he is located, serves as an altar of atonement, for it was stated: “And his land shall be an atonement for his people” (Dvarim / Deuteronomy 32:43). And in (a declaration of) punishments he stated, “upon an impure land you shall die” (Amos 7:17). And it is not comparable his absorption when alive to his to his absorption after death. And even so, the sages, would send their dead there; go out and learn from Yaakov Avinu and Yosef Hatzadik.
In his Beit Yisrael commentary some sources are provided for this Halacha. Ketuvot 111a, Rabbi Elazar, Kol Hadar with Rashi and Vilna Gaon’s commentary. Brachot 57a, HaOmed Arume with Rashi’s commentary Yevamot 64a, Rashi on Miketz Ramban to Vayikra / Leviticus 18:25 Ketuvot 111a, Rabbi Yirmiyahu bar Abba, in the name of Rabbi Yochanan, Kol Hamahalech… Ketuvot 111a, Rabbi Anan stated, Kol Hakavur … Ketuvot 111a The Gemara relates: Ulla was accustomed to ascend to Eretz Yisrael from time to time. However, he died outside of Eretz Yisrael. They came and said to Rabbi Elazar that Ulla had passed away. He said: Woe for you Ulla… Ketuvot 111a, the statements of Karna and Rabbi Chanina concerning Yaakov and Yosef
For important supplemental information about the mitzva of living in the land of Israel, see what is written in the article on this web site, Why the Holocaust?