Sefer HaChinuch ספר החינוך

To not leave from the meat of the Pesach sacrifice: To not leave any of the meat of the Pesach sacrifice to the next day (overnight), which is the fifteenth of Nissan, as it is stated (Exodus 12:10), “You shall not leave any of it over until morning.”

That which is written about its slaughter (Sefer HaChinukh 5) is from the roots of this commandment — to remember the miracles of Egypt. And the essence of that which we were commanded to not leave over from it, is that it is in the way of kings and ministers who do not need to leave over from their meals from one day to the next. And therefore it states that if there remains from it, one should burn it like something that he does not desire, in the way of the kings of the land. And all of this is to remember and establish in our hearts that at this time, God, may He be blessed, redeemed us and we became free and merited majesty and greatness.

The law of this commandment is in Pesachim. (See Mishneh Torah, Laws of Paschal Offering 9.)

And [it] is practiced by males and females at the time of the [Temple]. And one who transgresses it and leaves [it] over violates a negative commandment. And we do not give lashes for this negative commandment, since it is rectifiable by a positive commandment (Mishneh Torah, Laws of Paschal Offering 10:11) — as it is stated (Exodus 12:10), “and that which remains until the morning, you shall burn with fire.” And it is a law that we do not give lashes for [the transgression of] a negative commandment that is rectifiable by a positive commandment.