Exodus 13:4

13:4 On this day, in the month of Abib, you are going out.

Exodus 13:6-7

13:6 For seven days you must eat bread made without yeast, and on the seventh day there is to be a festival to the Lord. 13:7 Bread made without yeast must be eaten for seven days; no bread made with yeast shall be seen among you, and you must have no yeast among you within any of your borders.