How is trust in Hashem expressed?
Rashi: Do not say 'if I will not steal, or if I will give to Tzedakah to the Oni, how will I buy my needs?!'
Radak #1: Like it says after this, "do good"; the verse should be re-arranged Ase Tov u'Vetach ba'Shem Re'e Emunah v'Shechan Eretz. The reward is after the good deed.
Radak #2: The entire verse discusses doing good. There are three aspects to which good and evil apply to - the heart, the hand and the mouth. Trust in Hashem is Avodah of the heart, to trust in Him with all his heart and understand that He helps and makes stumble. This is unlike evildoers who trust only in their wealth and strength - "Ein Pachad Elokim l'Neged Einav" (36:2).
Mesilas Yesharim (Perek 19): One must guard himself from damagers created to punish Resha'im, but not to fear mishaps that occur over time. A foolish fear is to increase guarding on guarding and fear on fear, to make a fence for a fence that will lead to Bitul of Torah and Avodah.
Malbim: It is via doing good. Then he will have true success, unlike evildoers' success. A condition for success is that he knows that his deeds are good, and he is proper for success.
Why does it say "va'Ase Tov Shechan Eretz"?
Rashi: Do good, and you will dwell in the land many days.
Radak #1: Refer to 37:3:1:2.
Radak #2: "Va'Ase Tov" is doing good with the hand - giving Tzedakah, and doing His Mitzvos. Also refer to 37:3:3:3.
Malbim: Evildoers need to cross oceans and rivers to seek their success. You will dwell in the land - Hashem will give to you your food wherever you are!
What is the meaning of "u'Re'e Emunah"?
Rashi: You will eat and be financed as reward for trusting in Hashem, to rely on him and do good.
Radak #1: Refer to 37:3:1:2.
Radak #2: This is connected to "Shechan Eretz"; wherever you dwell, teach many to serve Hashem, like Avraham did. "Va'Yikra Sham Avram b'Shem Hashem" (Bereishis 13:4) - he taught many Hashem's ways. This is called grazing them - "v'Ra'u Eschem De'ah v'Haskel" (Yirmeyah 3:15). This is the primary Avodas Hashem with the mouth. One's own Avodas Hashem with the mouth - Yichud Hashem, prayer and praises is primarily in the heart, and even if he did not say them, he fulfilled his obligation. Teaching others is only via the mouth. The Vov in u'Re'e is superfluous, like "va'Yisa Avraham Es Einav" (Bereishis 22:4).
Malbim: One who does not trust in Hashem fears lest he lack his bread. He stores and does not benefit from his wealth. You will be like a lamb that grazes and trusts that the mountains will always sprout grass and herbs.
