A Matter Of Priority
‘Lands Shown By Hashem To Moses Are Subject To Tithes’
(Bava Basra 56a)
Rav Yehuda said in the name of Shmuel that only produce of the lands that Hashem showed Moses (on Mount Nevo before his death) are subject to terumos and ma’aseros.
Which Lands
The Gemara identifies the lands not showed to Moshe (aside from the obvious ones – like Canada, the Unites States, etc.) as being those of the Kenite, Kenizite, and Kadmonite. Although Hashem had promised Abraham (Genesis 13:14-17, 15:18-21) that these lands (ibid. 15:19) would ultimately belong to his descendants, they lack the sanctity of Eretz Yisrael since they were not conquered by Joshua – even should they be conquered at a later time.
Where You Tread
The Torah (Deuteronomy 11:24) states the following regarding the land of Israel: “Kol Hamakom asher tidrach kaf ragle’chem bo lachem yihyeh – Any place that the sole of your foot will tread will be yours.” Sifrei, cited by Tosafos (Gittin 82 s.v. “Kibbush Yachid”), explains that all lands conquered by Bnei Yisrael have the sanctity of Eretz Yisrael.
Mishneh LaMelech (Parshas Derachim, Darush 6; see also Rashi to our daf), citing the Sifrei, asks why these three lands, which were promised to Abraham, won’t acquire the sanctity of Eretz Yisrael after they are eventually conquered.
Yereisha L’Bnei Esav, Yereisha L’Bnei Lot
The gaon Rabbi Moshe Feinstein (Dibros Moshe, siman 38) explains that these lands are the inheritance of the children of Esau and Lot. And we find in Parshas Devarim (Deuteronomy 2:9-22) that Bnei Yisrael are warned not to provoke the children of Lot and Esau into war because their lands were given to them as an inheritance. The Ramban (Sefer Hamitzvos – Mitzvos Lo Ta’aseh, at the end) asserts that this prohibition applies to future generations as well. Since a prohibition prevents us from conquering these lands, they will never attain the sanctity of Eretz Yisrael, even when they ultimately belong to us in the times of Mashiach, says Rav Feinstein.