בְּכָל־דּוֹר וָדוֹר חַיָּב אָדָם לִרְאוֹת אֶת־עַצְמוֹ כְּאִלּוּ הוּא יָצָא מִמִּצְרַיִם, שֶׁנֶּאֱמַר: וְהִגַּדְתָּ לְבִנְךָ בַּיּוֹם הַהוּא לֵאמֹר, בַּעֲבוּר זֶה עָשָׂה ה' לִי בְּצֵאתִי מִמִּצְרַיִם. לֹא אֶת־אֲבוֹתֵינוּ בִּלְבָד גָּאַל הַקָּדוֹשׁ בָּרוּךְ הוּא, אֶלָּא אַף אוֹתָנוּ גָּאַל עִמָּהֶם, שֶׁנֶּאֱמַר: וְאוֹתָנוּ הוֹצִיא מִשָּׁם, לְמַעַן הָבִיא אוֹתָנוּ, לָתֶת לָנוּ אֶת־הָאָרֶץ אֲשֶׁר נִשָׁבַּע לַאֲבֹתֵינוּ.
In each and every generation, a person is obligated to see himself as if he left Egypt, as it is stated (Exodus 13:8); "For the sake of this, did the Lord do [this] for me in my going out of Egypt." Not only our ancestors did the Holy One, blessed be He, redeem, but rather also us [together] with them did he redeem, as it is stated (Deuteronomy 6:23); "And He took us out from there, in order to bring us in, to give us the land which He swore unto our fathers."
What does it mean, to feel as if we left Egypt? We cannot know how to feel this until we better understand how the Jews felt when they left. How did they feel? We can see traces of their emotions in the way they act and react during the Exodus and later, as well as the way they are commanded to act based on their emotions
הָא לַחְמָא עַנְיָא דִּי אֲכָלוּ אַבְהָתָנָא בְאַרְעָא דְמִצְרָיִם. כָּל דִכְפִין יֵיתֵי וְיֵיכֹל, כָּל דִצְרִיךְ יֵיתֵי וְיִפְסַח. הָשַּׁתָּא הָכָא, לְשָׁנָה הַבָּאָה בְּאַרְעָא דְיִשְׂרָאֵל. הָשַּׁתָּא עַבְדֵי, לְשָׁנָה הַבָּאָה בְּנֵי חוֹרִין.
This is the bread of destitution that our ancestors ate in the land of Egypt. Anyone who is famished should come and eat, anyone who is in need should come and partake of the Pesach sacrifice. Now we are here, next year we will be in the land of Israel; this year we are slaves, next year we will be free people.
Why do we start with Ha Lachma Anya? And what does this have to do with the second half of the text, Kol Dichsfin?
Exploring Exodus, Nachum Sarna
Finally, with the historicizing of religion comes the ethicizing of history. That is to say, history is used as a source of ethical teachings and as a motive force for social ethics. God's redemptive acts demand a corresponding imitative human response. A host of biblical passages gives eloquent expression to the idea that the experience of the slavery and liberation must become the wellspring of action. The following quotations amply illustrate the point