The Torah refers to Pesach as chag ha'matzos, while Chazal refer to Pesach as zman cheiruseinu (the time of our freedom). Rav Wolbe (Kol HaTorah vol. 61 pg. 57) elaborates on one aspect of the correlation between matzos and freedom. The Maharal writes that the reason matzah is also called lechem oni (bread of poverty) is because it contains only flour and water, the two basic ingredients of bread, while it lacks any additional ingredients. This bread is similar to the poor man who possesses nothing but himself. What does this mean for us?
The Gemara relates (Berachos 17a) that Rav Alechsandri would include a small statement in his prayers. "It is revealed and known before You that our will is to fulfill Your will; and what prevents us: the yeast in the dough (the yetzer hara) and our subjugation to foreign dominion." Why is the yetzer hara called "the yeast in the dough?" Yeast is an outside factor that causes the dough to rise more than it would have by itself. Likewise, the yetzer hara inflates the innate middos found inside every person beyond what he could and should reach. Every person needs a certain amount of self respect. Therefore, one who eats in the marketplace has invalidated himself from giving testimony in beis din since, "if he doesn't care about his own honor, he certainly won't care about another's honor (Kiddushin 40b)." However, the yetzer hara inflates the need for honor and causes a person to look for honor at every opportunity.
Similarly, jealousy is essential for without it no one would marry or build a house (see Mesilas Yesharim chap. 11). Once again, the yetzer hara inflates the jealousy until it encompasses everything his neighbor owns. Desire is also a positive trait because one who is lacking this middah wouldn't be able to fulfill the mitzvah of eating matzah since it would be considered achilah gasah. The problem is that the yetzer hara pumps up desire and changes it from a means to an end, into an end in and of itself, and thereby turning man into a pleasure-seeker. As a result, when a person becomes older and takes a good hard look at himself, he might be astounded to find out that his image and everything he portrays is totally foreign to his true self.
This is in regard to the yetzer hara that dwells inside a person. The Gra explains that there is yet another, external yetzer hara that we must contend with. This is the yetzer hara of being subjugated to foreign dominion. We live among the nations, and we are influenced by their way of life. One example is our need to keep up with the latest fashions lest we be looked upon as a relic from the past. It's amazing to think how some tailor in Paris fashions a garment, and within a week the entire world feels compelled to wear the figment of his imagination!
If we could succeed in uprooting the external foreign influences, and bursting the inflated bubble of middos created by the yetzer hara internally, we would experience a true sense of freedom. Accomplishing this allows one to perceive his true awesome stature, without any strings attached.
This is the meaning behind the Maharal's explanation of why matzoh is referred to as bread of poverty. We eat matzoh during the time of our freedom, because just as matzoh is free from all outside influences, so too, true freedom can only be experienced when one purges himself of all outside influences and perceives himself authentically. This is what we strive for on the Yom Tov of Pesach.
Chag Kasher V'Sameach!