Worship Works: The "Missing" Paragraphs of the V'Ahavta in Reform Liturgy

“The third paragraph of the Sh'ma is variously referred to by the Rabbis as parashat tzitzit, since it deals with the obligation to wear fringes on the four corners of one's garment that are to serve as reminders of God's commandments, and as Y'tziat Mitzrayim, 'the Exodus from Egypt,' since at the end it refers to God as the One who redeemed the Israelites from Egypt.... When the custom of wearing a tallit during morning prayers became less frequent among Reform Jews, this paragraph came to be dropped from the liturgy…. Now that many Reform Jews wear tallitot at morning prayers, Mishkan T'filah has restored the entire third paragraph as an option for those who wish to recite it--but only in the morning, since the tallit is not worn at night."
-- Sarason, Rabbi Richard S. Divrei Mishkan T'filah: Delving into the Siddur. CCAR Press, 2017. p 42-43.

דברים י״א:י״ג-כ״א

(יג) וְהָיָ֗ה אִם־שָׁמֹ֤עַ תִּשְׁמְעוּ֙ אֶל־מִצְוֺתַ֔י אֲשֶׁ֧ר אָנֹכִ֛י מְצַוֶּ֥ה אֶתְכֶ֖ם הַיּ֑וֹם לְאַהֲבָ֞ה אֶת־יְהוָ֤ה אֱלֹֽהֵיכֶם֙ וּלְעָבְד֔וֹ בְּכָל־לְבַבְכֶ֖ם וּבְכָל־נַפְשְׁכֶֽם׃ (יד) וְנָתַתִּ֧י מְטַֽר־אַרְצְכֶ֛ם בְּעִתּ֖וֹ יוֹרֶ֣ה וּמַלְק֑וֹשׁ וְאָסַפְתָּ֣ דְגָנֶ֔ךָ וְתִֽירֹשְׁךָ֖ וְיִצְהָרֶֽךָ׃ (טו) וְנָתַתִּ֛י עֵ֥שֶׂב בְּשָׂדְךָ֖ לִבְהֶמְתֶּ֑ךָ וְאָכַלְתָּ֖ וְשָׂבָֽעְתָּ׃ (טז) הִשָּֽׁמְר֣וּ לָכֶ֔ם פֶּ֥ן יִפְתֶּ֖ה לְבַבְכֶ֑ם וְסַרְתֶּ֗ם וַעֲבַדְתֶּם֙ אֱלֹהִ֣ים אֲחֵרִ֔ים וְהִשְׁתַּחֲוִיתֶ֖ם לָהֶֽם׃ (יז) וְחָרָ֨ה אַף־יְהוָ֜ה בָּכֶ֗ם וְעָצַ֤ר אֶת־הַשָּׁמַ֙יִם֙ וְלֹֽא־יִהְיֶ֣ה מָטָ֔ר וְהָ֣אֲדָמָ֔ה לֹ֥א תִתֵּ֖ן אֶת־יְבוּלָ֑הּ וַאֲבַדְתֶּ֣ם מְהֵרָ֗ה מֵעַל֙ הָאָ֣רֶץ הַטֹּבָ֔ה אֲשֶׁ֥ר יְהוָ֖ה נֹתֵ֥ן לָכֶֽם׃ (יח) וְשַׂמְתֶּם֙ אֶת־דְּבָרַ֣י אֵ֔לֶּה עַל־לְבַבְכֶ֖ם וְעַֽל־נַפְשְׁכֶ֑ם וּקְשַׁרְתֶּ֨ם אֹתָ֤ם לְאוֹת֙ עַל־יֶדְכֶ֔ם וְהָי֥וּ לְטוֹטָפֹ֖ת בֵּ֥ין עֵינֵיכֶֽם׃ (יט) וְלִמַּדְתֶּ֥ם אֹתָ֛ם אֶת־בְּנֵיכֶ֖ם לְדַבֵּ֣ר בָּ֑ם בְּשִׁבְתְּךָ֤ בְּבֵיתֶ֙ךָ֙ וּבְלֶכְתְּךָ֣ בַדֶּ֔רֶךְ וּֽבְשָׁכְבְּךָ֖ וּבְקוּמֶֽךָ׃ (כ) וּכְתַבְתָּ֛ם עַל־מְזוּז֥וֹת בֵּיתֶ֖ךָ וּבִשְׁעָרֶֽיךָ׃ (כא) לְמַ֨עַן יִרְבּ֤וּ יְמֵיכֶם֙ וִימֵ֣י בְנֵיכֶ֔ם עַ֚ל הָֽאֲדָמָ֔ה אֲשֶׁ֨ר נִשְׁבַּ֧ע יְהוָ֛ה לַאֲבֹתֵיכֶ֖ם לָתֵ֣ת לָהֶ֑ם כִּימֵ֥י הַשָּׁמַ֖יִם עַל־הָאָֽרֶץ׃ (ס)

Deuteronomy 11:13-21

(13) If, then, you obey the commandments that I enjoin upon you this day, loving the LORD your God and serving Him with all your heart and soul, (14) I will grant the rain for your land in season, the early rain and the late. You shall gather in your new grain and wine and oil— (15) I will also provide grass in the fields for your cattle—and thus you shall eat your fill. (16) Take care not to be lured away to serve other gods and bow to them. (17) For the LORD’s anger will flare up against you, and He will shut up the skies so that there will be no rain and the ground will not yield its produce; and you will soon perish from the good land that the LORD is assigning to you. (18) Therefore impress these My words upon your very heart: bind them as a sign on your hand and let them serve as a symbol on your forehead, (19) and teach them to your children—reciting them when you stay at home and when you are away, when you lie down and when you get up; (20) and inscribe them on the doorposts of your house and on your gates— (21) to the end that you and your children may endure, in the land that the LORD swore to your fathers to assign to them, as long as there is a heaven over the earth.

“...It is not necessary to read this paragraph of the Sh’ma as a literal statement about divine reward and punishment. In a world whose survival depends partly on the human capacity to value creation and care for it wisely, it is possible to interpret the passage more naturalistically. If we are able to develop an ecological consciousness, if we treat the earth with respect, if we are aware that we are embedded in a great web of life which God is the ultimate source and sustainer, then the earth will bear fruit for us and the rain will come in its season. But if we believe we can trample on or transcend the constraints of nature, if we forget the sacredness of all things and make idols of our own wealth and power, ‘the earth will not grants its produce,’ and both we and our world may perish.”
-- Plaskow, Rabbi J. (2011). If you carefully heed my commandments. In Rabbi L. A. Hoffman, My People's Prayer Book: Traditional Prayers, Modern Commentaries (7th Printing ed., Vol. 1 -- The Sh'ma and Its Blessings, pp. 105-110). Woodstock, VT: Jewish Lights Publishing