Passover from the Bible to the Temples
The focus is on the paschal offering.
Excerpted with permission from Every Person's Guide to Passover (Jason Aronson, Inc).
Hag HaPesach: The Feast of the Paschal Lamb
Hag HaPesach (the festival of the paschal lamb)--the sacrificial rite of the paschal lamb and its consumption--was the main feature of the ancient Passover ceremony that ushered in the holiday. This unique ritual included the slaughtering of the lamb on the afternoon of the 14th of Nisan (Leviticus 23:5). This was an exception to the general rule that all festival offerings are to be sacrificed on the day of the festival.
Furthermore, the lambs were slaughtered by the Israelites, privately by each family, and the priests poured the blood on the base of the altar. All other offerings were generally slaughtered by the priests. When the [Second] Temple was destroyed [in 70 CE], all sacrifice eventually ceased, and only the Samaritans continued to bring the offering in their own community. To this day, they slaughter a lamb at sunset, read Exoduschapter 12, and eat the Passover meal after midnight together with unleavened bread (matzah) and bitter herbs.
The explanation for the uniqueness of the Passover sacrificial rite may be found in its commemorative aspects. The Bible repeatedly emphasized this facet of Passover, "And this day shall be for you a memorial…" (Exodus12:14); "And Moses said to the people: remember this day in which you come out from Egypt, out of the house of bondage…" (Exodus13:3); "You shall remember what Adonai your God did to Pharaoh…" (Deuteronomy7: 18); "that you may remember the day when you come out of the land of Egypt all the days of your life" (Deuteronomy16:3). These verses are a clear indication that the general function of the Passover pageantry was to serve as a constant reminder to the Israelites of their struggle against slavery and their wondrous deliverance from Egyptian bondage.
The festival of the paschal lamb was ushered in on the evening of the 14th of Nisan. On that night, the Israelites were ordered to eat the paschal lamb, and several restrictive rules were added to this feast. "And they shall eat the flesh in that night, roasted with fire; with unleavened bread and bitter herbs they shall eat it" (Exodus12:8). They were not to eat it rare or boiled in water (Exodus 12:9). They were not to leave the meat over past the conclusion of the night (Exodus 12: 10). They were not to break any of the bones of the lamb (Exodus 12:46). No alien sojourner, hired servant, or uncircumcised person may eat the meat of the paschal lamb (Exodus 12:43-45). And finally, the feast was to be held in one house, and no part of the meat was to be taken outside the house (Exodus 12:46).