GEMARA: The Sages taught: If his son is wise and knows how to inquire, his son asks him. And if he is not wise, his wife asks him. And if even his wife is not capable of asking or if he has no wife, he asks himself. And even if two Torah scholars who know the halakhot of Passover are sitting together and there is no one else present to pose the questions, they ask each other.
רָשָׁע מָה הוּא אוֹמֵר? מָה הָעֲבוֹדָה הַזּאֹת לָכֶם. לָכֶם – וְלֹא לוֹ. וּלְפִי שֶׁהוֹצִיא אֶת עַצְמוֹ מִן הַכְּלָל כָּפַר בְּעִקָּר. וְאַף אַתָּה הַקְהֵה אֶת שִׁנָּיו וֶאֱמוֹר לוֹ: "בַּעֲבוּר זֶה עָשָׂה ה' לִי בְּצֵאתִי מִמִּצְרָיִם". לִי וְלֹא־לוֹ. אִלּוּ הָיָה שָׁם, לֹא הָיָה נִגְאָל:
What does the evil [son] say? "'What is this worship to you?' (Exodus 12:26)" 'To you' and not 'to him.' And since he excluded himself from the collective, he denied a principle [of the Jewish faith]. And accordingly, you will blunt his teeth and say to him, "'For the sake of this, did the Lord do [this] for me in my going out of Egypt' (Exodus 13:8)." 'For me' and not 'for him.' If he had been there, he would not have been saved.