Numbers 28:17

There shall be a feast on the fifteenth day of this month; unleavened bread shall be eaten for seven days.

Leviticus 23:6

The Feast of Unleavened Bread to the Lord is on the fifteenth day of the same month; for seven days you shall eat unleavened bread.

Exodus 12:15-17

[In the celebration of the Passover in future years,] seven days you shall eat unleavened bread, but on the first day you shall remove the leaven from your houses [because it represents the spread of sin]; for whoever eats leavened bread on the first day through the seventh day, that person shall be cut off and excluded from [the atonement made for] Israel.

Exodus 13:6

For seven days you shall eat unleavened bread, and on the seventh day there shall be a feast to the Lord.

Exodus 23:15

You shall observe the Feast of Unleavened Bread; for seven days you shall eat unleavened bread, as I commanded you, at the appointed time in the month of Abib, for in it you came out of Egypt. No one shall appear before Me empty-handed [but you shall bring sacrificial offerings].

Exodus 34:18

“You shall observe the Feast of Unleavened Bread (Passover). For seven days you shall eat unleavened bread, as I have commanded you, at the appointed time in the month of Abib; for in the month of Abib you came out of Egypt.

Deuteronomy 16:3-8

You shall not eat leavened bread with it; instead, for seven days you shall eat the Passover with unleavened bread, the bread of affliction (for you left the land of Egypt in haste); [do this] so that all the days of your life you may remember [thoughtfully] the day when you came out of the land of Egypt.

Treasury of Scripture Knowledge

Summary

And in the fifteenth day of this month is the feast: seven days shall unleavened bread be eaten.

Bible References

General references

Exodus 12:15
[In the celebration of the Passover in future years,] seven days you shall eat unleavened bread, but on the first day you shall remove the leaven from your houses [because it represents the spread of sin]; for whoever eats leavened bread on the first day through the seventh day, that person shall be cut off and excluded from [the atonement made for] Israel.
Exodus 13:6
For seven days you shall eat unleavened bread, and on the seventh day there shall be a feast to the Lord.
Leviticus 23:6
The Feast of Unleavened Bread to the Lord is on the fifteenth day of the same month; for seven days you shall eat unleavened bread.