Siman 484

One who has neighbors who are unlearned people who do not know how to recite kiddush and perform the Seder, and he is compelled to perform the Seder for them, how shall he act? He performs the Seder for himself in his house first until after his meal, and until after he recites Birkat HaMazon. For before Birkat HaMazon it is forbidden for him to uproot himself even if he wishes to eat there, as this was only permitted for the sake of a passing mitzvah, as I wrote in siman 178 and 179. And here he can go after Birkat HaMazon. And after Birkat HaMazon he should go, and Hallel he should say afterward, because the neighbors want to eat, and also so that midnight shall not pass. And when he finishes with them to teach them the Seder – he shall return to his house and say Hallel, and drink the fourth cup. And in this we are not concerned regarding an interruption, and also perhaps it will be after midnight, for it is not an absolute requirement, and especially since he was occupied with the mitzvah to teach them the Seder. And if he wishes – he may also finish Hallel in his house.

And how shall he act with them? For behold, he is forbidden to eat and drink further, as he has already eaten the afikoman. Furthermore, one may not eat in two places, as I have written in siman 478. He should perform Kiddush for them and they shall drink the cup, for Kiddush is a blessing of the mitzvot, as we hold that even if one has fulfilled his obligation, he may fulfill the obligation of others. It is not like a blessing of enjoyment, where we require that he also enjoys it himself, and if not, he cannot bless on behalf of another. For regarding mitzvot, all Israel are guarantors for one another, and it is as if the obligation is incumbent upon his own person. Therefore, he may perform Kiddush for them, even though he does not need it for himself. And also the blessing "borei peri hagafen," even though it is a blessing of enjoyment, nevertheless, since it is a necessity for Kiddush, it is like a blessing of the mitzvot like Kiddush (end of the third chapter of Rosh Hashanah). And so too the blessing "hamotzi" for the eating of matzah is like a blessing of the mitzvot (ibid.), and he may bless on their behalf. And even the blessing "borei peri ha'adamah" for the karpas, even though it is only a distinction for the children, nevertheless, since it is an enactment of the sages, it is like a blessing of the mitzvot. And there are those who cast doubt on this as is explained in the Tur, but the Rosh decided thus as the halacha. However, regarding Birkat HaMazon, even though it is an obligation, nevertheless, it is forbidden to bless on their behalf unless he ate with them, for it is written: "And you shall eat and be satisfied and you shall bless" — and not one who did not eat. For so it is stated in the Yerushalmi, third chapter of Berakhot (halacha 3).

And thus he shall do: he recites kiddush for them and they drink the cup. And they wash their hands, and dip the karpas, and he recites the blessing on their behalf "borei peri ha'adamah," and they answer "amen" and eat. And he explains the Haggadah to them in a language they understand until "ga'al Yisrael." And he recites the blessing over the second cup, and they drink. And they wash their hands, and he recites "hamotzi" and "al achilat matzah," and they answer "amen" and eat. And afterward he recites the blessing "al achilat maror," and they eat. And he shall make "korech" for them and they eat. And they finish the meal, and they recite birkat hamazon themselves for the reason that has been explained. And if they are unable—he dictates to them word for word, and they repeat after him. For this is not called "discharging their obligation," but rather like a minor who dictates to an adult.

And so he goes to all the houses and does so. And afterward he goes to his house and finishes the Hallel, and drinks the fourth cup. And regarding Hallel—they are all able to come to him and hear Hallel, for Hallel does not necessarily have to be at the location of the Seder. And know that this which we said, that at first he should finish his Seder in his house—this is not a necessity. For if he wishes, he may first perform the Seder for them, and he shall not taste anything, and afterward he shall perform the Seder for himself. Rather, if he wishes—he may first perform it for himself and afterward for them, as I have written. (See Magen Avraham subsection 2 in the name of the Shiltei Gibborim, that this which was explained that it is forbidden to eat with them—this is when he has already eaten the afikoman at his place. But if he has not yet eaten—it is permitted, for during the rest of the meal we are not concerned about two locations. But the Tur in the name of Rav Kohen Tzedek forbids eating in two locations during the entire meal, see there and see Turei Zahav.)