'Unleavened Bread' in the Bible

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

You must eat unleavened bread for six days. On the seventh day there is to be a solemn assembly to the Lord your God, and you must not do any work.

“All your males are to appear three times a year before the Lord your God in the place He chooses: at the Festival of Unleavened Bread, the Festival of Weeks, and the Festival of Booths. No one is to appear before the Lord empty-handed.