Cut off - The penalty inflicted on those who transgressed the command may be accounted for on the ground that it was an act of rebellion; but additional light is thrown upon it by the typical meaning assigned to leaven by our Lord, Matthew 16:6.
Related Commentaries of Exodus 12:15
Exodus 12:15
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.