It is prohibited by Torah law to own chametz (leaven) on Pesach. Therefore we search and destroy chametz before Pesach. In most homes the process of cleaning begins weeks before Pesach. The house is scoured from top to bottom to remove all traces of chametz.

Bedikat chametz is done the night before Pesach, Nissan 14 immediately after nightfall. If it is too difficult to search the whole house on one night the search can be started earlier according to the laws of bedikat chametz. However, the blessing is only said on the night of the 14^th.

Before the search the blessing of 'al biur chametz' is recited as found in the Haggadah or Siddur. From the time the blessing is said until the after the search one should not say anything not relevant to the search.

When there is more than one building to search, one blessing suffices. One person says the blessing for all the searchers, they listen to the blessing and say "amen." Then they split up and search the different buildings.

Any chametz not found during the search is declared null and ownerless (hefker): "All chametz, leaven and leavened bread, that is in my possession which I have not seen, removed or is unknown to me, should be annulled and considered ownerless like the dust of the earth." This declaration is traditionally said in Aramaic as found in the Haggadah or Siddur. However, one who doesn't understand Aramaic must say it in a language he understands.

The search should be conducted by the light of a candle, in order to look in all the nooks and crannies. If the candle might cause damage, such as a carpeted area, one may use a flashlight.

It is preferable that the owner of the property conduct the search himself. Nevertheless, he may appoint someone else to search on his behalf.

Any place chametz might have been put during the year must be searched. Therefore, one must also check one's pockets.

There is a custom that ten pieces of chametz are "planted" in the rooms to be searched. If you hide ten and find nine, just keep searching! The ten pieces remind us of the ten plagues.

The following morning, it is forbidden to eat chametz after the fourth hour. One may continue to derive other benefit from the chametz until the end of the fifth hour. Before this time, the chametz must be burned and again nullified. Since the times vary from city to city, an Orthodox rabbi should be consulted for the exact times in your area.

The second nullification is: "All chametz, leaven and leavened bread, that is in my possession, whether I have seen it or not, whether I have removed it or not, should be annulled and considered ownerless like the dust of the earth."

Chametz is symbolic of the "evil inclination" which we "seek and destroy."