וַתַּרְבֶּ֖ה אֶת־תַּזְנוּתֶ֑יהָ לִזְכֹּר֙ אֶת־יְמֵ֣י נְעוּרֶ֔יהָ אֲשֶׁ֥ר זָנְתָ֖ה בְּאֶ֥רֶץ מִצְרָֽיִם׃
Yet she multiplied her harlotries, remembering the days of her youth, wherein she had played the harlot in the land of Egypt.
Sefer HaChinukh
It is from the roots of this commandment [that it is] so that the Jews will always remember the miracle that God did for them during the exodus from Egypt - that He killed all of their first-born, as it is written.