structural:scholar_edition, information:filtering, quality:corruption, linguistic:paraphrasing, stylistic:style_transfer
In the Book of Exodus

In the Book of Exodus, the Israelites are enslaved in ancient Egypt. Yahweh, the god of the Israelites, appears to Moses in a burning bush and commands Moses to confront the Pharaoh. To show his power, Yahweh inflicts a series of ten plagues on the Egyptians, culminating in the plague of the death of the firstborn.

Moses said, “Thus says יהוה: Toward midnight I will go forth among the Egyptians, and every first-born in the land of Egypt shall die, from the first-born of Pharaoh who sits on his throne to the first-born of the slave girl who is behind the millstones; and all the first-born of the cattle. And there shall be a loud cry in all the land of Egypt, such as has never been or will ever be again;

Before this final plague, Yahweh commands Moses to tell the Israelites to mark a lamb 's blood above their doors so God will pass over them and the plague of the death of the firstborn will not afflict them.

The biblical regulations for the observance of the festival require that all leavening be disposed of before the beginning of the 15th of Nisan according to Exodus 13:7 An unblemished lamb or goat, known as the Passover sacrifice or "Paschal Lamb", is to be set apart on 10th Nisan, and slaughtered at dusk as 14th Nisan ends in preparation for the 15th of Nisan when it will be eaten after being roasted. The literal meaning of the Hebrew is "between the two evenings". It is then to be eaten "that night", 15th Nisan, roasted, without the removal of its internal organs with unleavened bread, known as matzah, and bitter herbs known as maror. Nothing of the sacrifice on which the sun rises by the morning of the 15th of Nisan may be eaten, but must be burned.

The biblical regulations of the original Passover at the time of the Exodus only also include how the meal was to be eaten: "your loins girded, your sandals on your feet, and your staff in your hand; and you shall eat it hurriedly: it is a passover offering to יהוה."

The biblical requirements of slaying the Paschal lamb in the individual homes of the Hebrews and smearing the blood of the lamb on their doorways were celebrated in Egypt. However, once Israel was in the wilderness and the Tabernacle was in operation, a change was made in those two original requirements. Passover lambs were to be sacrificed at the door of the Tabernacle and no longer in the homes of the Jews. No longer, therefore, could blood be smeared on doorways.