וַיְסַפֵּר אֶל אָבִיו וְאֶל אֶחָיו וַיִּגְעַר בּוֹ אָבִיו וַיֹּאמֶר לוֹ מָה הַחֲלוֹם הַזֶּה אֲשֶׁר חָלָמְתָּ הֲבוֹא נָבוֹא אֲנִי וְאִמְּךָ וְאַחֶיךָ לְהִשְׁתַּחֲוֹת לְךָ אָרְצָה
He told it to his father and to his brothers, and his father rebuked him saying, "'What is this dream that you have dreamed? Shall I and your mother and your brothers bow down on the ground to you?"
Why did Joseph’s first dream only have eleven sheaves of wheat representing his brothers but his second dream had eleven stars (representing his brothers) plus the sun and the moon (representing his parents)? Rabbi Joseph B. Soloveitchik explains that the dream of wheat reflected Joseph’s future material success. For such a thing his parents would never prostrate themselves. The dream of heavenly bodies, however, referred to Joseph’s future success in spiritual matters. For such a thing, his parents would happily acknowledge a person’s greatness. (From Yemei Zikaron, cited in the Mesoras HaRav Chumash.)