We are beginning siman 15. The Chayei Adam writes that if one does have any wine nor chamer medina for havdalah, and does not anticipate obtaining any before Sunday night, it is sufficient for them to recite atah chonantanu in shemoneh esrei and to say baruch hamavdil bein kodesh lechol. Since this person is unable to recite havdalah on a kos, this havdalah is sufficient and allows them to begin eating immediately.
If they anticipate being able to obtain havdalah wine before Sunday night, some hold the person cannot eat until making havdalah. The Mishnah Berurah points out that some opinions hold that if one will not obtain wine until after chatzos on Sunday, they do not have to wait and can rely on the havdalah of davening on motzei Shabbos.
Nevertheless, if one is very hungry or weak, they can rely on the havdalah in shemoneh esrei and eat immediately. However, one who does not have these concerns must wait to eat until making havdalah.
In siman 16, the Chayei Adam again clarifies one cannot begin eating from bein hashmashos until making havdalah. However, if one began eating before bein hashmashos; meaning, they said hamotzi before shkia, they can continue as long as they would like. The only exception is that if people at the seudah suggested that they recite havdalah, it may be considered a hesech hadaas (interruption) for drinks; meaning, if one wished to drink further, they would have to recite a new bracha. However, the Chayei Adam concludes that it is a safeik whether suggesting to recite havdalah is considered a hesech hadaas or not, so we apply the rule of safeik brachos lehakeil and one would not make a new bracha. Certainly, lechatchilla it would be preferable to avoid the situation.
Summary
- If one will not obtain liquid for havdalah until Sunday night, they can eat immediately. If they will obtain liquid before Sunday night, they must refrain from eating until they make havdalah.
- The Mishnah Berurah brings an opinion that if one will not obtain liquid for havdalah by Sunday chatzos, they can eat immediately on Motzei Shabbos.
- In these cases, if one is very hungry or weak, they may rely on the havdalah of shemoneh esrei and eat immediately.
- One cannot eat after the beginning of bein hashmashos until they make havdalah., unless they began a hamotzi meal before shkia.