Exodus 34:25

Thou shalt not offer the blood of my sacrifice with leavened bread; neither shall the fat of my sacrifice remain until the morning. sacrifice: or, feast

And ye shall let nothing of it remain until the morning; and that which remaineth of it until the morning ye shall burn with fire.

Ye shall eat nothing leavened; in all your habitations shall ye eat unleavened bread.

And the flesh of the sacrifice of his peace offerings for thanksgiving shall be eaten the same day that it is offered; he shall not leave any of it until the morning.

Thou shalt eat no leavened bread with it; seven days shalt thou eat unleavened bread therewith, even the bread of affliction; for thou camest forth out of the land of Egypt in haste: that thou mayest remember the day when thou camest forth out of the land of Egypt all the days of thy life.

Purge out therefore the old leaven, that ye may be a new lump, as ye are unleavened. For even Christ our passover is sacrificed for us: is sacrificed; or, is slain Therefore let us keep the feast, not with old leaven, neither with the leaven of malice and wickedness; but with the unleavened bread of sincerity and truth. the feast: or, holyday

And if ought of the flesh of the consecrations, or of the bread, remain unto the morning, then thou shalt burn the remainder with fire: it shall not be eaten, because it is holy.

They shall leave none of it unto the morning, nor break any bone of it: according to all the ordinances of the passover they shall keep it.

And they shall eat the flesh in that night, roast with fire, and unleavened bread; and with bitter herbs they shall eat it.