In the first month you are to eat unleavened bread, from the evening of the fourteenth day until the evening of the twenty-first day.

Matthew 26:17
On the first day of the Feast of Unleavened Bread, the disciples came to Jesus and asked, "Where do you want us to prepare for You to eat the Passover?"

Exodus 12:2
"This month is the beginning of months for you; it shall be the first month of your year.

Leviticus 23:5
The Passover to the LORD begins at twilight on the fourteenth day of the first month.

Numbers 28:16
The fourteenth day of the first month is the LORD's Passover.

Joshua 5:10
On the evening of the fourteenth day of the month, while the Israelites were camped at Gilgal on the plains of Jericho, they kept the Passover.

In the first month, on the fourteenth day of the month at even, you shall eat unleavened bread, until the one and twentieth day of the month at even.