וּמָ֣ה הָ֠אָרֶץ הַשְּׁמֵנָ֨ה הִ֜וא אִם־רָזָ֗ה הֲיֵֽשׁ־בָּ֥הּ עֵץ֙ אִם־אַ֔יִן וְהִ֨תְחַזַּקְתֶּ֔ם וּלְקַחְתֶּ֖ם מִפְּרִ֣י הָאָ֑רֶץ וְהַ֨יָּמִ֔ים יְמֵ֖י בִּכּוּרֵ֥י עֲנָבִֽים׃
토지의 후박과 수목의 유무니라 담대하라 또 그 땅 실과를 가져오라 하니 그 때는 포도가 처음 익을 즈음이었더라
Rashi on Numbers
היש בה עץ WHETHER THERE ARE TREES IN IT [OR NOT] — i.e. whether there is a righteous man amongst them who will protect them by his merits (cf. Bava Batra 15a).
Sforno on Numbers
השמנה היא, does it possess riches, surpluses, as Moses said in Deuteronomy 8,9 לא במסכנות תאכל בה לחם, “where you will eat bread without having to stint.”
Or HaChaim on Numbers
ומה הארץ השמנה היא, and what about the land, is it fat, etc.? Did this land impart its fat to the fruit it produced without becoming impoverished, or was it such that after each harvest it became impoverished, רזה, so that it had to be given a year's rest before being sown again?