|וְנָתְנָה הָאָרֶץ פִּרְיָהּ, וַאֲכַלְתֶּם לָשֹׂבַע; וִישַׁבְתֶּם לָבֶטַח, עָלֶיהָ.|
|כ וְכִי תֹאמְרוּ, מַה-נֹּאכַל בַּשָּׁנָה הַשְּׁבִיעִת: הֵן לֹא נִזְרָע, וְלֹא נֶאֱסֹף אֶת-תְּבוּאָתֵנוּ.|
|כא וְצִוִּיתִי אֶת-בִּרְכָתִי לָכֶם, בַּשָּׁנָה הַשִּׁשִּׁית; וְעָשָׂת, אֶת-הַתְּבוּאָה, לִשְׁלֹשׁ, הַשָּׁנִים.|
It's unclear when exactly the farmer will ask this question, "Mah nocahl ba'shana ha'shevi'is?" (see Ramban, Kil Yakar) The sixth year is a regular farming year, so the farmer has no need for alarm. By the time the seventh year rolls around, the farmer's storehouses will be overflowing with the harvest from the previous year; the farmer again has no cause for concern.
The Alter of Navardok in Madreigas ha'Adam answers that it's not in the sixth year or seventh year that the farmer will worry -- it's in the first year. From day one the farmer knows that a shemita is coming, so he spends six years planning and worrying about how to get through that one year.
The farmer who does this may keep shemita to the letter of the law, but he circumvents the entire spirit of the law. The lesson of shemita is that our parnasa depends on Hashem, not only on our own efforts. The Midrash extols the level of bitachon demonstrated by simple farmers who keep shemita. What kind of bitachon does it show if you scrimp and save a little bit each year because you don't trust that you will find the resources to get through that seventh year of shemita?
"V'nasna ha'aretz pirya, v'achaltem la'sova," says the Alter, is not a bracha -- it's a mitzvah. Enjoy the bounty of the land, eat your fill of produce, trust that there will be enough for the seventh year. Don't scrimp and save like your life depends on it to get through shemita.
This is Navardok bitachon in its purest form, no histhtadlus required. For many of us, myself included, it's easier to swallow a model of bitachon that allows or even obligates us to make our own histadlus before relying on Hashem.
The Alter reveals a fascinating paradox inherent in this model of bitachon: What happens if the farmer ignores this directive and does spend his time socking away grain for the lean year? "V'tzivisi es birchasi..." only applies to those who exercise their bitachon and fulfill the "mitzvah" of "V'achaltem la'sova..." If you sock away the grain instead -- no bracha, no bountiful harvest The situation becomes a self-fulfilling prophecy -- the farmer who spends his time socking away grain for six years will not receive a bracha and in year six will suddenly say, "Aha! You see, I was right to store away what I can, because this year's crop is no different than any other year!" It's only the farmer who makes the initial commitment and takes the plunge with bitachon who will be zocheh to see the fruits of his effort in that sixth year.
By definition, the value of bitachon is not something that can be proven beforehand -- those who exercise bitachon will enjoy its rewards; those who don't will see exactly the results they expect to justify their lacking.