Exodus 13:8

בעבור זה FOR THE SAKE OF THIS — for the sake that I should carry out His commands, such as this Passover offering, this unleavened bread and this bitter herb (cf. Mekhilta). עשה ה' לי GOD DID FOR ME — Here is an indication of the reply to be given to the wicked son: that one should say to him, “God did for me” — and one should not say “what God did לנו, for us” — thus implying “not for thee”, for if thou hadst been there (in Egypt) thou wouldst not have been regarded as worthy of being redeemed (Mekhilta).

וְהִגַּדְתָּ֣ לְבִנְךָ֔ בַּיּ֥וֹם הַה֖וּא לֵאמֹ֑ר בַּעֲב֣וּר זֶ֗ה עָשָׂ֤ה יְהֹוָה֙ לִ֔י בְּצֵאתִ֖י מִמִּצְרָֽיִם׃

And thou shalt relate to thy son on that day, saying, This is done because of that which the Lord did to me when I came out of Miżrayim.