The night before Pesach, all Jews are commanded to search their homes for chometz by candlelight and collect the pieces to be burned the next morning.
There is a beautiful story of The Alter Rebbe, Rabbi Schneur Zalman of Liadi, author of “Shluchan Oruch HaRav” and the “Tanya,” and his search for chometz in 5525 (1765). The Alter Rebbe had traveled to Mezeritch earlier that year to study under the great Maggid. He returned home to his wife shortly before Pesach, fully prepared to apply all of his newly learned spiritual lessons to his daily life – especially the lessons he learned regarding bedikas chometz.
The day before Pesach, the Alter Rebbe was so busy preparing to do the mitzvah of bedikas chometz, that he bearly ate (although he did not fast, because it is prohibited to fast during Nissan). Though his home only had one small room, the Alter Rebbe’s search lasted the entire night.
After finally finishing his search, the Alter Rebbe gave a kabbalistic interpretation of the words of the Mishnah: “Or L’Arbah Asar Bodkin Es HaChametz L’Ohr HaNeir” (On the eve of the fourteenth, we search for chometz by the light of a candle).
The Alter Rebbe explained, “thirteen” is numerically equal to the word “Echad” (one). Oneness is the knowledge of G-d and His existence. When one is on this level, there is no need to search. “Fourteen” symbolizes our seven emotional attributes—Chessed (loving kindness), Gevurah (severity), Tiferes (harmony), Netzach (victory), Hod (splender), Yesod (foundation) and Netzach (majesty), which are mirrored in the animal soul and the G-dly soul, where a search is required.
According to the Mishnah, the search must be by candlelight, for a candle represents the soul: “Ki Ner Hashem Nishmas Adam” (The candle of G-d is the soul of man). This search must include one’s entire self, all aspects of one’s soul and personality, just like the physical search for chometz which must include all of the crevices of one’s home.
This inner search is symbolic of the difference between chometz and matzah; chometz rises, while matzah is flat. The rising of the chometz is like the inflated ego of one who is full of self-love and self-importance. Matzah, in contrast, represents humility (bittul), and one’s desire to submit oneself to the will of G-d.
Chometz and matzah also have another difference. They share two of the same letters, but chometz contains the letter “Ches”, while matzah contains the letter “Hey”. Ches and Hey both look similar, having three sides with an opening on the bottom. In Chassidic texts, this represents an opening for sin, as hinted in the verse “Sin crouches at the opening” (Genesis 4:7). What differentiates the hey and the ches, is that the hey has an opening at the top, which represents rising above and beyond one’s self to do teshuvah.
This manifests itself in the inner struggle of man. A “chometz’dike” person, one consumed with self-importance, is more likely to give in to desire and rationalize sin. However, a person who is like “matzah,” and has bittul, is less likely to sin and will feel remorse after commiting a sin, using the “opening” to do teshuvah.