(ג) אִם־בְּחֻקֹּתַ֖י תֵּלֵ֑כוּ וְאֶת־מִצְוֺתַ֣י תִּשְׁמְר֔וּ וַעֲשִׂיתֶ֖ם אֹתָֽם׃
(ד) וְנָתַתִּ֥י גִשְׁמֵיכֶ֖ם בְּעִתָּ֑ם וְנָתְנָ֤ה הָאָ֙רֶץ֙ יְבוּלָ֔הּ וְעֵ֥ץ הַשָּׂדֶ֖ה יִתֵּ֥ן פִּרְיֽוֹ׃
(ה) וְהִשִּׂ֨יג לָכֶ֥ם דַּ֙יִשׁ֙ אֶת־בָּצִ֔יר וּבָצִ֖יר יַשִּׂ֣יג אֶת־זָ֑רַע וַאֲכַלְתֶּ֤ם לַחְמְכֶם֙ לָשֹׂ֔בַע וִֽישַׁבְתֶּ֥ם לָבֶ֖טַח בְּאַרְצְכֶֽם׃
(ו) וְנָתַתִּ֤י שָׁלוֹם֙ בָּאָ֔רֶץ וּשְׁכַבְתֶּ֖ם וְאֵ֣ין מַחֲרִ֑יד וְהִשְׁבַּתִּ֞י חַיָּ֤ה רָעָה֙ מִן־הָאָ֔רֶץ וְחֶ֖רֶב לֹא־תַעֲבֹ֥ר בְּאַרְצְכֶֽם׃
(ז) וּרְדַפְתֶּ֖ם אֶת־אֹיְבֵיכֶ֑ם וְנָפְל֥וּ לִפְנֵיכֶ֖ם לֶחָֽרֶב׃
(ח) וְרָדְפ֨וּ מִכֶּ֤ם חֲמִשָּׁה֙ מֵאָ֔ה וּמֵאָ֥ה מִכֶּ֖ם רְבָבָ֣ה יִרְדֹּ֑פוּ וְנָפְל֧וּ אֹיְבֵיכֶ֛ם לִפְנֵיכֶ֖ם לֶחָֽרֶב׃
(ט) וּפָנִ֣יתִי אֲלֵיכֶ֔ם וְהִפְרֵיתִ֣י אֶתְכֶ֔ם וְהִרְבֵּיתִ֖י אֶתְכֶ֑ם וַהֲקִימֹתִ֥י אֶת־בְּרִיתִ֖י אִתְּכֶֽם׃
(י) וַאֲכַלְתֶּ֥ם יָשָׁ֖ן נוֹשָׁ֑ן וְיָשָׁ֕ן מִפְּנֵ֥י חָדָ֖שׁ תּוֹצִֽיאוּ׃
(יא) וְנָתַתִּ֥י מִשְׁכָּנִ֖י בְּתוֹכְכֶ֑ם וְלֹֽא־תִגְעַ֥ל נַפְשִׁ֖י אֶתְכֶֽם׃
(יב) וְהִתְהַלַּכְתִּי֙ בְּת֣וֹכְכֶ֔ם וְהָיִ֥יתִי לָכֶ֖ם לֵֽאלֹהִ֑ים וְאַתֶּ֖ם תִּהְיוּ־לִ֥י לְעָֽם׃
(יג) אֲנִ֞י יְהוָ֣ה אֱלֹֽהֵיכֶ֗ם אֲשֶׁ֨ר הוֹצֵ֤אתִי אֶתְכֶם֙ מֵאֶ֣רֶץ מִצְרַ֔יִם מִֽהְיֹ֥ת לָהֶ֖ם עֲבָדִ֑ים וָאֶשְׁבֹּר֙ מֹטֹ֣ת עֻלְּכֶ֔ם וָאוֹלֵ֥ךְ אֶתְכֶ֖ם קֽוֹמְמִיּֽוּת׃
(3) If you follow My laws and faithfully observe My commandments, (4) I will grant your rains in their season, so that the earth shall yield its produce and the trees of the field their fruit. (5) Your threshing shall overtake the vintage, and your vintage shall overtake the sowing; you shall eat your fill of bread and dwell securely in your land. (6) I will grant peace in the land, and you shall lie down untroubled by anyone; I will give the land respite from vicious beasts, and no sword shall cross your land. (7) You shall give chase to your enemies, and they shall fall before you by the sword. (8) Five of you shall give chase to a hundred, and a hundred of you shall give chase to ten thousand; your enemies shall fall before you by the sword. (9) I will look with favor upon you, and make you fertile and multiply you; and I will maintain My covenant with you. (10) You shall eat old grain long stored, and you shall have to clear out the old to make room for the new. (11) I will establish My abode in your midst, and I will not spurn you. (12) I will be ever present in your midst: I will be your God, and you shall be My people. (13) I the LORD am your God who brought you out from the land of the Egyptians to be their slaves no more, who broke the bars of your yoke and made you walk erect.
Shemos 15:26, Shemos 19:5-6, Shemos 20:12, Shemos 23:22-25 (26-31), Shemos 30:12, Devarim 11:13-21, etc.
They all mention physical rewards.
The Jewish people believe in a doctrine of spiritual reward for their efforts, and yet, in the places where their contract discusses reward, only physical reward is mentioned.
How is it possible that we could expect more than physical rewards when the Torah clearly delineates physical reward and nothing else?
Kidushin 39b - שכר מצוות בהאי עלמא ליכא
No reward is mentioned in the Torah at ALL, just the things we need to do the job we're already supposed to do. That's not a reward, that's just an expense account.
The TRUE reward isn't mentioned because we're supposed to serve Lishmah. If it were mentioned, we would be OBLIGATED to serve for reward.
The physical reward that IS mentioned isn't an obligation to serve for rain, it's the obligation to serve in order to have the opportunity to serve more, the very definition of Lishmah.
(If you do what you're supposed to do, God will give you what you need to keep doing it.)
רבינו האי ז״ל אמר כי לא הוצרך הכתוב לפרש דבר העוה״ב כי היה ידוע בהעתק' ולפי דעתי שהתורה נתנה לכל לא לאחד לבדו ודבר העוה״ב לא יבינו א' מני אלף כי עמוק הוא...והמשכיל יבין
Sefer HaIkarim points out that the Torah talks about incorporeality ("Lo Ra'Isem Kol Temunah"), but there's a difference between not imagining a physical object (negation) and imagining a nonphysical reward (affirmation).
The Torah doesn't need to tell us natural things. Spiritual reward is VERY natural, physical reward is counterintuitive.
Rambam explains the process of reward and prophecy as very objective systems of personal development.
"The benefits of your religion are NOTHING compared to the benefits of the other religions!!"
"A) their rewards all happen after this world, making them unfalsifiable, and B) clearly, even the members of the other religions want THIS world because nobody wants to die."
The Torah guarantees a reward that people really want. (What does the horse want, a hundred dollars or a bag of oats?)
Saadia Gaon (Emunos veDe'os 9:2) brings evidences from Tanakh and other places of righteous people who had terrible lives (Yitzchak, Chananya/Mishael/Azaryah, Daniel, Moshe, Eliyahu, Elisha, Sodom, Israel's subjugation to the nations, babies in Midyan and Mabul).
Derashos haRan, Drush 1
A) We guarantee spiritual reward here in a physical world, a fortiori we will get it once divested of our physical body
B) Unlike other religions which have unfalsifiable promises, Judaism's is falsifiable. This phenomenon is recorded in Tanakh and is theologically consistent.
At-Tur 52:17-20
Indeed, the righteous will be in gardens and pleasure, Enjoying what their Lord has given them, and their Lord protected them from the punishment of Hellfire. [They will be told], "Eat and drink in satisfaction for what you used to do." They will be reclining on thrones lined up, and We will marry them to fair women with large, [beautiful] eyes.
Matthew 6:19-21
“Stop storing up treasures for yourselves on earth, where moths and rust destroy and thieves break in and steal. Instead, store up treasures for yourselves in heaven, where moths and rust don’t destroy and thieves don’t break in and steal. Your heart will be where your treasure is."
Ramban, Devarim 11:13
The rewards of the Torah are directed at the entire nation, not at any individual Jews. Spiritual rewards are beneficial only for individual people, physical reward, however, is enjoyed nationally.