"And do not shear the firstborn of your sheep"—Deuteronomy 15:19.
It is forbidden to shear an animal designated for sacrifice.
"And the entire assembly of the congregation of Israel shall slaughter it in the afternoon"—Exodus 12:6.
Every individual is commanded to offer [or participate on a group that is offering] the Paschal Sacrifice on the afternoon of the fourteenth of Nissan [the eve of Passover]—even if this day falls on the Shabbat.
"You shall not offer the blood of my sacrifice with leavened bread"—Exodus 23:18.
It is forbidden to have chametz (leavened bread) in one's possession from the onset of the time when the Paschal Offering is brought—noon of the fourteenth of Nissan [the eve of Passover].
This prohibition applies to all those who are participating in the eating of the sacrifice, the priest who slaughters it, the priest who sprinkles its blood on the altar, and the priest who offers its fats on the altar.
"Neither shall the fat of My sacrifice remain until the morning"—Exodus 23:18.
It is forbidden to leave unsacrificed the fats of the Paschal Offering that are designated to be burnt on the altar, until they become invalid for offering [i.e., until the following morning].
