Deuteronomy 16:4
And there shall be no leavened bread seen with thee in all thy coast seven days; neither shall there any thing of the flesh, which thou sacrificedst the first day at even, remain all night until the morning.
Exodus 12:10
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.
Exodus 34:25
Thou shalt not offer the blood of my sacrifice with leaven; neither shall the sacrifice of the feast of the passover be left unto the morning.
Exodus 13:7
Unleavened bread shall be eaten seven days; and there shall no leavened bread be seen with thee, neither shall there be leaven seen with thee in all thy quarters.
Exodus 12:15
Seven days shall ye eat unleavened bread; even the first day ye shall put away leaven out of your houses: for whosoever eateth leavened bread from the first day until the seventh day, that soul shall be cut off from Israel.
Exodus 12:8
And they shall eat the flesh in that night, roast with fire, and unleavened bread; and with bitter herbs they shall eat it.