Rectification of Sin

Eating matza which is made out of wheat is a rectification for the sin of Adam who ate from the Tree of Knowledge which was, according to the Talmud wheat (סנהדרין ע, א).

It is for this reason that matzah is called michla d’mheimnusa—the food of faith, because the sin of Adam was considered a denial of Hashem’s oneness, and the rectification is through strengthening our faith.

(זרע קודש פסח כט,א)