(Genesis 13:14) "And the LORD said to Abram, after Lot had separated from him." Rabbi Yehuda said: Abraham our father was angry when his nephew parted from him. The Holy One, blessed be He, said: To everyone He cleaves, but to Lot his nephew He does not cleave [that is, the divine word that had been withheld now returns]. Rabbi Nechemiah says: The Holy One, blessed be He, had been displeased with him during the time that Lot walked with him. The Holy One, blessed be He, said: Thus I said to him, "To your seed I will give this land" (Genesis 13:15), and he clings to Lot his nephew in order to make him his heir. If so, let him go and bring two mannequins from the market and make them heirs of what is his, just as he wants his nephew. This is what is written, "Cast out the scoffer, and contention goes out" (Proverbs 22:10) "cast out the scoffer" this is Lot, of whom it is written, "and there was strife between the herdsmen of Abram's cattle" (Genesis 13:7); "and quarrel and shame cease" (Proverbs 22:10), as in "and Abram said to Lot, let there be no quarrel" (Genesis 13:8). (Genesis 13:16) "And I will make your seed as the dust of the earth." Just as the earth stretches from one end of the world to the other, so your children shall be from one end of the world to the other. And just as the dust of the earth is blessed only through water, so your children are blessed only through the merit of the Torah, which is compared to water. And just as the dust of the earth wears away vessels of metal, so Israel: the nations cease and Israel endures. And just as the dust of the earth is made for treading, so your children are made to be trodden by the kingdoms. This is what is written, "and I will put it in the hand of those who afflict you" (Isaiah 51:23) those who afflict you, yet even so it is for your good, for they shake your sins off you, as you say, "with showers you soften it, you bless its growth" (Psalms 65:11). "Who said to your soul, bow down that we may pass over" (Isaiah 51:23) what would they do? They would lay them down in the open streets and make them lie down and pass over them. And this is a good sign: just as this street wears out those who come and go and yet it endures, so your children wear out the nations and they endure.
God Spoke to Abraham Only After Lot Departed From Him
Yalkut Shimoni on Torah 70:5
(בראשית יג יד) וַה' אָמַר אֶל אַבְרָם אַחֲרֵי הִפָּרֶד לוֹט מֵעִמּוֹ. רַבִּי יְהוּדָה אָמַר, כַּעַס הָיָה לְאַבְרָהָם אָבִינוּ כְּשֶׁפֵּרֵשׁ בֶּן אָחִיו מִמֶּנּוּ אָמַר הַקָּדוֹשׁ בָּרוּךְ הוּא, לַכֹּל הוּא מִדַּבֵּק, וּלְלוֹט בֶּן אָחִיו אֵינוֹ מִדַּבֵּק. רַבִּי נֶחֶמְיָה אוֹמֵר, כַּעַס הָיָה לוֹ מֵהַקָּדוֹשׁ בָּרוּךְ הוּא בְּשָׁעָה שֶׁהָיָה לוֹט מְהַלֵּךְ עִמּוֹ, אָמַר הַקָּדוֹשׁ בָּרוּךְ הוּא, כָּךְ אָמַרְתִּי לוֹ "לְזַרְעֲךָ נָתַתִּי אֶת הָאָרֶץ הַזֹּאת" וְהוּא מִדַּבֵּק אֶת לוֹט בֶּן אָחִיו כְּדֵי לְיָרְשׁוֹ אִם כֵּן יֵלֵךְ וְיָבִיא לוֹ שְׁנֵי פְּרַסְתְּקִין מִן הַשּׁוּק וְיוֹרִישֵׁם אֶת שֶׁלּוֹ, כְּמוֹ שֶׁהוּא רוֹצֶה בֶּן אָחִיו, הֲדָא הוּא דִּכְתִיב, (משלי כב, י) "גָּרֵשׁ לֵץ וְיֵצֵא מָדוֹן" "גָּרֵשׁ לֵץ וְיֵצֵא מָדוֹן", זֶה לוֹט וַיְּהִי רִיב בֵּין רוֹעֵי מִקְנֵה אַבְרָם (שם) "וְיִשְׁבּוֹת דִּין וְקָלוֹן", (לעיל פסוק ח) וַיֹּאמֶר אַבְרָם אֶל לוֹט אַל נָא תְהִי מְרִיבָה. (בראשית יג טז) וְשַׂמְתִּי אֶת זַרְעֲךָ כַּעֲפַר הָאָרֶץ. מַה הָאָרֶץ מִסּוֹף הָעוֹלָם וְעַד סוֹפוֹ, כָּךְ בָּנֶיךָ מִסּוֹף הָעוֹלָם וְעַד סוֹפוֹ. וּמַה עֲפַר הָאָרֶץ אֵין מִתְבָּרֵךְ אֶלָּא בְּמַיִם, כָּךְ בָּנֶיךָ אֵין מִתְבָּרְכִין אֶלָּא בִּזְכוּת הַתּוֹרָה שֶׁנִּמְשְׁלָה לְמַיִם וּמַה עֲפַר הָאָרֶץ מְכַלֶּה כְּלֵי מַתָּכוֹת, כָּךְ יִשְׂרָאֵל הָעַכּוּ"ם בְּטֵלִים וְהֵם קַיָּמִים. וּמַה עֲפַר הָאָרֶץ עָשׂוּי דַּיִשׁ כָּךְ בָּנֶיךָ עֲשׂוּיִין דַּיִשׁ לְמַלְכֻיּוֹת, הֲדָא הוּא דִּכְתִיב, "וְשַׂמְתִּיהָ בְּיַד מוֹגַיךְ", אִלִּין דִּמְמִיגִין לְךָ וַאֲפִלּוּ כֵּן לְטוֹבָתָךְ מְקַשְׁקְשִׁין לְךָ מִן חוֹבֵיךְ כֶּהַאִיךְ דְאַתְּ אַמְרֵתְ, (תהלים סה, יא) "בִּרְבִיבִים תְּמוֹגֲגֶנָה צִמְחָהּ תְּבָרֵךְ". (ישעיה שם) "אֲשֶׁר אָמְרוּ לְנַפְשֵׁךְ שְׁחִי וְנַעֲבוֹרָה", מָה הָיוּ עוֹשִׂים, מַרְבִּיצִין אוֹתָן בְּפַלְטְרָאוֹת וּמַעֲבִירִין וְרָדִין עֲלֵיהֶן וְהָא סִימָן טָב מַה פַּלְטְיָא זוֹ מְכַלָּה אֶת הָעוֹבְרִים וְאֶת הַשָּׁבִים וְהִיא קַיֶּמֶת כָּךְ בָּנַיךְ מְכַלִּים אֶת הָעַכּוּ"ם וְהֵן קַיָּמִין.