Deuteronomy 16:7

3 You must not eat leavened bread with it; for seven days you are to eat with it unleavened bread, the bread of affliction, because you left the land of Egypt in haste—so that you may remember for the rest of your life the day you left the land of Egypt.

4 No leaven is to be found in all your land for seven days, and none of the meat you sacrifice in the evening of the first day shall remain until morning.

5 You are not to sacrifice the Passover animal in any of the towns that the LORD your God is giving you.

6 You must only offer the Passover sacrifice at the place the LORD your God will choose as a dwelling for His Name. Do this in the evening as the sun sets, at the same time you departed from Egypt.

7 And you shall roast it and eat it in the place the LORD your God will choose, and in the morning you shall return to your tents.

8 For six days you must eat unleavened bread, and on the seventh day you shall hold a solemn assembly to the LORD your God, and you must not do any work.

9 You are to count off seven weeks from the time you first put the sickle to the standing grain.

10 And you shall celebrate the Feast of Weeks to the LORD your God with a freewill offering that you give in proportion to how the LORD your God has blessed you,

11 and you shall rejoice before the LORD your God in the place He will choose as a dwelling for His Name—you, your sons and daughters, your menservants and maidservants, and the Levite within your gates, as well as the foreigner, the fatherless, and the widows among you.

Read all of Deuteronomy 16