John Calvin on Exodus 12:42

42. It is a night to be much observed. He shows that the Israelites have good cause for sacrificing to God with a solemn ceremony year by year for ever, and for celebrating the memory of that night; and that the Passover was instituted in token of their gratitude. But this admonition was very useful, in order that the Israelites should retain the legitimate use of this solemn feast-day, and that it might not grow into a mere cold ceremony, as is often the case; but that rather they might profitably, and to the advancement of their piety, exercise themselves in this emblem of their redemption. At the same time, he teaches that this so inestimable a benefit was not to be celebrated in one, or two, or three generations, but that as long as the people should remain it was worthy of eternal remembrance, and that it might never be forgotten, the Passover was to be sacredly observed.

Moreover we must remark, that the generations of the ancient people were brought to an end by the coming of Christ; because the shadows of the Law ceased when the state of the Church was renewed, and the Gentiles were gathered into the same body.