Passover is, probably, the most joyful of our festivals. This has to do not only with an overall feeling of finally awakening nature but also with the message of hope that fills both the Pesach rituals and the words surrounding them.
As I age, I start to read every text around me closer and slower than before. This comes not only from the desire to compensate for every line in the Torah that has ever been skipped out of boredom and laziness but also from the newly-acquired skill of examination of words and concepts with far greater precision and degree of attention. Such is the young children, marveling at the world around them; such are the elderly, who have the means and the time to stop and reflect.
I have read this particular verse, maybe, hundreds of times without noticing the everlasting message of hope that it conveys. וְהָיָ֕ה כִּֽי־יֹאמְר֥וּ אֲלֵיכֶ֖ם בְּנֵיכֶ֑ם מָ֛ה הָעֲבֹדָ֥ה הַזֹּ֖את לָכֶֽם (Exodus 12;26). The message of hope here is twofold. The children of Israel receive a promise of the future generations, coming from them. Moreover, these generations will be inquisitive enough to ask their ancestors about the meaning of the Pesach ritual.
Chizkuni explains that the questions will certainly arise as the Pesach ritial is not repeated on Pesach itself. The blood on the doorposts separated children of Israel from their neighbours but since it has served its purpose we don’t need it any longer. The children of Israel are not merely promised to have children but their descendants are going to keep studying the Torah.