(ז) כִּי ה' אֱלֹקֶיךָ מְבִיאֲךָ אֶל אֶרֶץ טוֹבָה אֶרֶץ נַחֲלֵי מָיִם עֲיָנֹת וּתְהֹמֹת יֹצְאִים בַּבִּקְעָה וּבָהָר. (ח) אֶרֶץ חִטָּה וּשְׂעֹרָה וְגֶפֶן וּתְאֵנָה וְרִמּוֹן אֶרֶץ זֵית שֶׁמֶן וּדְבָשׁ. (ט) אֶרֶץ אֲשֶׁר לֹא בְמִסְכֵּנֻת תֹּאכַל בָּהּ לֶחֶם לֹא תֶחְסַר כֹּל בָּהּ אֶרֶץ אֲשֶׁר אֲבָנֶיהָ בַרְזֶל וּמֵהֲרָרֶיהָ תַּחְצֹב נְחֹשֶׁת. (י) וְאָכַלְתָּ וְשָׂבָעְתָּ וּבֵרַכְתָּ אֶת ה' אֱלֹקֶיךָ עַל הָאָרֶץ הַטֹּבָה אֲשֶׁר נָתַן לָךְ.
(7) For the Adonai your God brings you into a good land, a land of brooks of water, of fountains and depths, springing forth in valleys and hills; (8) a land of wheat and barley, and vines and fig-trees and pomegranates; a land of olive-trees and honey; (9) a land wherein you shall eat bread without scarceness, you shall not lack any thing in it; a land whose stones are iron, and out of whose hills you may dig brass. (10) And you shalt eat and be satisfied, and bless the Adonai you God for the good land which God has given you.
When a person eats and is satisfied, he is liable to reject God as the verse says: lest you eat and become satiated…and forget the Lord, your God (Deuteronomy 8:12–14). Therefore, God commanded that when one eats and is satiated, he should mention God with thanks and remember that “He is the one who gives you strength for accomplishments” (Deuteronomy 8:18)
-R. Meir Simcha Hakohen from Dvinsk, Deuteronomy 8:10
Rabbi R. Meir Simcha Hakohen from Dvinsk (1843–1926, Rabbi and scholar from Eastern Europe) notes the constant possibility that material comfort can create a sense of complacency and arrogance. It is often easier to turn to God when hungry than after finishing a lavish meal. The Torah addresses this potential pitfall by placing the grace after the meal. In many ways, people have a much greater need for a reminder about God and our religious commitments after eating than before.
-Rabbi Yizchak Blau