ESV - 6 Seven days you shall eat unleavened bread, and on the seventh day there shall be a feast to the Lord.
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According to bible, "Seven days thou shalt eat unleavened bread, and in the seventh day shall be a feast to the LORD. 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 13:6 - 13:7 KJV).