Halakhah sa Exodo 34:25: Mishneh Torah, Leavened and Unleavened Bread, Sefer HaChinukh & Mishneh Torah, Negative Mitzvot

There is a positive commandment from the Torah to remove the hametz before the time that it is forbidden for consumption as it says (Shemot 12:15) "On the first day, remove the leavened from your homes." From the oral law, they learned that the first day refers to the 14th of Nissan. A proof to this matter is what is stated in the Torah: (Shemot 34:25) "Do not slaughter the animal with hametz in your possession." This means to say do not slaughter [the korban pesach] while the hametz exists. The day of the slaughtering the korban pesach is the 14th day following midday.

To not leave the entrails of the Pesach sacrifice to stay overnight: Not to leave the entrails of the Pesach sacrifice until the morning, [such] that they not be sacrificed, and [so] become disqualified with this leaving over and become called notar (what is left over); as it is stated (Exodus 23:18), “and the fat of My festival offering shall not be left lying until morning.” And the same is true of other portions to be burned in other sacrifices. And the language of Mekhilta DeRabbi Yishmael 23:18 is “‘The fat shall not be left lying’ — the verse comes to teach that the fats are disqualified by lying over.” And this preventing was already repeated in another place, as it is stated (Exodus 34:25), “and the sacrifice of the festival of Pesach shall not be left lying until morning.”

Not to do work with cattle set apart for sacrifice, as it is said, “Thou shalt do no work with the firstling^*By extensive interpretation, the rule is applied to all cattle set apart for any sacrifices.^*By extensive interpretation, the rule is applied to all cattle set apart for any sacrifices. of thy bullock….” (Deut. 15:19).