(א) בראשית אָמַר רַבִּי יִצְחָק לֹֹֹֹֹא הָיָה צָרִיךְ לְהַתְחִיל אֶת הַתּוֹרָה אֶלָּא מֵהַחֹדֶשׁ הַזֶּה לָכֶם,שֶׁהִיא מִצְוָה רִאשׁוֹנָה שֶׁנִּצְטַוּוּ בָּהּ יִשׂרָאֵל, וּמַה טַּעַם פָּתַח בִּבְרֵאשִׁית? מִשׁוּם כֹּחַ מַעֲשָׂיו הִגִּיד לְעַמּוֹ לָתֵת לָהֶם נַחֲלַת גּוֹיִם (תהילים קי”א), שֶׁאִם יֹאמְרוּ אוּמוֹת הָעוֹלָם לְיִשְׁרָאֵל לִסְטִים אַתֶּם, שֶׁכִּבַּשׁתֶּם אַרְצוֹת שִׁבְעָה גוֹיִם, הֵם אוֹמְרִים לָהֶם כָּל הָאָרֶץ שֶׁל הַקָּבָּ"ה הִיא, הוּא בְרָאָהּ וּנְתָנָהּ לַאֲשֶׁר יָשָׁר בְּעֵינָיו, בִּרְצוֹנוֹ נְתָנָהּ לָהֶם, וּבִרְצוֹנוֹ נְטָלָהּ מֵהֶם וּנְתָנָהּ לָנוּ:
(1) בראשית IN THE BEGINNING — Rabbi Isaac said: The Torah which is the Law book of Israel should have commenced with the verse (Exodus 12:2) “This month shall be unto you the first of the months” which is the first commandment given to Israel. What is the reason, then, that it commences with the account of the Creation? Because of the thought expressed in the text (Psalms 111:6) “He declared to His people the strength of His works (i.e. He gave an account of the work of Creation), in order that He might give them the heritage of the nations.” For should the peoples of the world say to Israel, “You are robbers, because you took by force the lands of the seven nations of Canaan”, Israel may reply to them, “All the earth belongs to the Holy One, blessed be He; He created it and gave it to whom He pleased. When He willed He gave it to them, and when He willed He took it from them and gave it to us” (Yalkut Shimoni on Torah 187).
(ו) כֹּ֣חַ מַ֭עֲשָׂיו הִגִּ֣יד לְעַמּ֑וֹ לָתֵ֥ת לָ֝הֶ֗ם נַחֲלַ֥ת גּוֹיִֽם׃ (ז) מַעֲשֵׂ֣י יָ֭דָיו אֱמֶ֣ת וּמִשְׁפָּ֑ט נֶ֝אֱמָנִ֗ים כָּל־פִּקּוּדָֽיו׃ (ח) סְמוּכִ֣ים לָעַ֣ד לְעוֹלָ֑ם עֲ֝שׂוּיִ֗ם בֶּאֱמֶ֥ת וְיָשָֽׁר׃ (ט) פְּד֤וּת ׀ שָׁ֘לַ֤ח לְעַמּ֗וֹ צִוָּֽה־לְעוֹלָ֥ם בְּרִית֑וֹ קָד֖וֹשׁ וְנוֹרָ֣א שְׁמֽוֹ׃ (י) רֵ֘אשִׁ֤ית חָכְמָ֨ה ׀ יִרְאַ֬ת יְהוָ֗ה שֵׂ֣כֶל ט֭וֹב לְכָל־עֹשֵׂיהֶ֑ם תְּ֝הִלָּת֗וֹ עֹמֶ֥דֶת לָעַֽד׃
6) He revealed to His people His powerful works, in giving them the heritage of nations.
(7) His handiwork is truth and justice; all His precepts are enduring, (8) well-founded for all eternity, wrought of truth and equity. (9) He sent redemption to His people; He ordained His covenant for all time; His name is holy and awesome. (10) The beginning of wisdom is the fear of the LORD; all who practice it gain sound understanding. Praise of Him is everlasting.
Now this is a great principle, for it is impossible to mention in the Torah all aspects of man's conduct with his neighbors and friends, and all his various transactions, and the ordinances of all societies and countries. But since He mentioned many of them…he reverted to state in a general way that, in all matters, one should do what is good and upright; including even compromise and going beyond the requirements of the law. (Nachmanides ad loc., Chavel translation)