'Unleavened' in the Bible

Now on the first day of the feast of unleavened bread, the disciples came to Jesus, saying, Where wilt thou that we prepare for thee to eat the passover?

Now the passover and the feast of unleavened bread was after two days. And the chief priests and the scribes were seeking how they might seize him by subtlety and kill him.

And the first day of unleavened bread, when they slew the passover, his disciples say to him, Where wilt thou that we go and prepare, that thou mayest eat the passover?

Now the feast of unleavened bread, which is called the passover, drew nigh,

And the day of unleavened bread came, in which the passover was to be killed.

And seeing that it was pleasing to the Jews, he went on to take Peter also: (and they were the days of unleavened bread:)

but we sailed away from Philippi after the days of unleavened bread, and we came to them to Troas in five days, where we spent seven days.

Purge out the old leaven, that ye may be a new lump, according as ye are unleavened. For also our passover, Christ, has been sacrificed;

so that let us celebrate the feast, not with old leaven, nor with leaven of malice and wickedness, but with unleavened bread of sincerity and truth.