Siman 432

And before he begins to search – he shall recite a blessing, just as one recites a blessing over all the mitzvot. And here there is a positive Torah commandment of "but on the first day you shall remove...", and a rabbinic positive commandment that they enacted to search on the night of the fourteenth. And the mitzvah extends from the search until the next day after the removal. And the blessing is: "Blessed... who has sanctified us with His mitzvot and commanded us concerning the removal of chametz." And if he recited the blessing "to remove chametz" – he has fulfilled his obligation, but initially they enacted "concerning the removal" (Gemara Pesachim 7b). And they enacted the phrasing of "removal" because it includes both: the search and the removal; and it also includes the nullification, for he nullifies immediately after the search the chametz that he did not see, as will be explained (and see Turei Zahav subsection 1). And if he began to search without a blessing – he shall recite the blessing as long as he has not finished his search, for as long as he has not finished it is called "prior to its performance." And if he finished and did not recite the blessing – he shall recite the blessing the next day at the time of the burning, and the nullification of the next day when he nullifies also the chametz that he sees as will be explained, for behold this is the primary completion of its mitzvah. And it is proper to wash his hands before the search. However, if he searches immediately after Maariv – he does not need to wash his hands, for behold he washed them before the Maariv prayer. And the nullification that follows the search will be explained in siman 434.

It is forbidden to speak between the blessing and the beginning of the search, as with all blessings over mitzvot or over pleasures. If one spoke regarding matters concerning the search – he does not need to repeat the blessing, as this is like "bring salt" for "HaMotzi," where one does not need to repeat the blessing. However, if he spoke regarding matters not concerning the search – he must repeat the blessing. Nevertheless, once he has begun to search – there is no prohibition according to the law if he spoke in the middle of the search. For this is like one who interrupts in the middle of a meal with speech, which is of no concern to us, since he has begun to do the thing over which he blessed. In any event, it is proper to be careful in this as well, not to interrupt with speech until after the conclusion of the search. And this is not because of the interruption, but rather so that he may set his heart to search in all the places where chametz is brought in.

And there is one who wishes to say that according to the law it is forbidden to interrupt even after he has begun to search. And it is not similar to a meal, for there he can stop and not eat further. But regarding the search – behold, he is compelled to search all of it. And if so, regarding that which remains – it constitutes an interruption (Taz, subsection 1). But it does not appear so, for is it that for every small portion of the search one must recite a blessing? Behold, he can fulfill his obligation with his blessing even for several houses. And if so, just as in a meal the blessing of "Hamotzi" applies also to what he eats after the interruption, so too regarding the search.

And with one blessing he can search several houses. And if the householder wishes—he may place members of his household near him at the time he recites the blessing, and they shall answer "Amen," and each man shall scatter to his place to search, relying on the blessing that the householder recited. For ten who perform one mitzvah—one blessing serves them all. And if the householder commands another to search—that other person recites the blessing, even though the mitzvah is not incumbent upon him—nevertheless, a person's agent is like himself. Just as with milah, where the obligation is upon the father of the son, yet the mohel recites the blessing (Magen Avraham, subsection 6). And the mitzvah is greater when performed by him than by his agent. Nevertheless, when he appoints an agent—he should appoint an agent who is subject to the obligation and of sound mind, and not minors. And walking from house to house—does not constitute an interruption (Chok Yaakov). And it is customary to place pieces of hard chametz, so that the searcher will find them, so that his blessing will not be in vain. And if he did not place them—it does not hinder, for every person's intent is to destroy if any is found. And it is customary to place ten hard pieces in the windows. And we do not recite the blessing "Shehecheyanu" over the search for chametz, as it is not a mitzvah that contains joy. Furthermore: since it pertains to the essence of Pesach, he will indeed recite "Shehecheyanu" over the cup of Kiddush (and see in the Tur and Beit Yosef).

And know: that there are those who ask according to our custom, wherein the women clean the rooms and the chests, and all the places in which chametz was used, several days before Pesach; and on the night of the fourteenth no chametz is found anymore, except for what they set aside to eat at night and the next morning, and these are guarded, if so, what is the matter of the bedikah for which we recite a blessing? For behold, all the places have already been checked? However, this is not a question. First: for we have already explained that the blessing also includes the nullification, and the removal of the next day. Furthermore: for behold, until tomorrow before midday there is still more chametz that is required to be removed, that which remains from the eating of the night and the morning. And if so, it is automatically as if one stands in the middle of the bedikah. And we have already explained that when one stands in the middle of the bedikah – he may recite a blessing, as I wrote in section 1. And see in the next siman, section 13.