On the evening before Passover, make a formal search of the home and all its sorrounding properties while holding a lit candle.
It is customary to put pieces of hard bread in various places some time before the search, so that the one who searches will find them.
According to the Kabbalah, one should place 10 pieces.
Before starting the search, the following blessing is recited: Blessed are You, Lord, our G‑d, King of the universe, who has sanctified us with His commandments and commanded us concerning the removal of chametz.
One is to search by candlelight in all hidden places, even cracks in the floor.
One is not to speak between the blessing and the beginning of the search, even concerning the search itself.
Throughout the search one should not speak about anything that is not relevant to the search.
Members of the household should stand nearby to hear the blessing, with each one then searching his own place without speaking in between.
Take heed to search first in the room nearest the place where the blessing was heard, and not to go to another room immediately after the blessing.
After the search one must be careful that the chametz retained to be eaten or to be burnt in the morning, be put in a safe place, so that it not be carried about and thereby crumbled and spread by children or rodents.
After the search one must also nullify [the chametz he may have overlooked] and say:
All leaven and anything leavened that is in my possession, which I have neither seen nor removed, and about which I am unaware, shall be considered nullified and ownerless as the dust of the earth.
On the morning before Passover, in the fifth hour of the day (calculated from sunrise), one should make a special fire and burn the chametz and nullify it.
For the nullification of the chametz say:
All leaven and anything leavened that is in my possession, whether I have seen it or not, whether I have observed it or not, whether I have removed it or not, shall be considered nullified and ownerless as the dust of the earth.
The ten pieces are to be burnt, and the following is said during the burning of the chametz:
May it be Your will, Lord, our G‑d and G‑d of our fathers, that just as I remove the chametz from my house and from my possession, so shall You remove all the extraneous forces.
Remove the spirit of impurity from the earth, remove our evil inclination from us, and grant us a heart of flesh to serve You in truth.
Make all the sitra achara, all the kelipot, and all wickedness be consumed in smoke, and remove the dominion of evil from the earth. Remove with a spirit of destruction and a spirit of judgment all that distress the Shechina, just as You destroyed Egypt and its idols in those days, at this time. Amen, Selah.
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