Even after Yom Kippur ends, it remains forbidden to do melakha, eat, or drink until after havdala, as we take leave of the holy day through havdala. The recitation of hadvala (“Ata ḥonantanu”) in the berakha of Ata Ḥonen in the Amida of Ma’ariv permits melakha, but eating and drinking remain prohibited until the recitation of havdala over wine. If one did not pray Ma’ariv but recited the phrase “Barukh ha-mavdil bein kodesh le-ḥol” (“Blessed is the One Who distinguishes between the sacred and the mundane”), he may do melakha, but he still may not eat or drink until he hears havdala recited over wine (SA 624:1; Peninei Halakha: Shabbat 8:8).
The havdala after Yom Kippur includes the berakhot over wine and over fire, as well as the berakha of havdala itself. We omit the verses that are customarily recited before havdala after Shabbat (“Hinei Kel…”) as well as the berakha over spices. The berakha over spices is included in havdala after Shabbat to comfort the soul after the departure of the neshama yeteira (lit. “expanded soul”). After Yom Kippur, however, the soul is in a state of joy, not pain, because sins have been forgiven. Even when Yom Kippur is on Shabbat, according to many authorities, the berakha on spices is omitted. One who nevertheless wishes to recite this berakha may do so after he finishes havdala and drinks a bit of wine.
Unlike on Saturday night, when we recite havdala over a flame we light at that moment, after Yom Kippur we make havdala using a flame that has been burning throughout Yom Kippur. On Motza’ei Shabbat, the purpose of the berakha on fire is to thank God for the fire that was discovered by Adam on the first Motza’ei Shabbat, when he took two stones and struck them together, producing fire, for which he praised and thanked God. To commemorate this, we too thank God for fire on Motza’ei Shabbat. However, after Yom Kippur, we recite the berakha over fire because during Yom Kippur we were not allowed to utilize fire, but it is now permitted to us once again. Therefore, the berakha must be recited specifically over a flame that was burning on Yom Kippur but could not be used because of the prohibition of using fire. Therefore, it is customary to light a yahrzeit candle before Yom Kippur, for use during havdala at the end of the day (SA 624:4; MB ad loc. 7).
Although le-khatḥila the berakha should be recited over a flame that was lit before Yom Kippur, bedi’avad, one who forgot to light a candle before the fast or one whose flame was extinguished may make havdala using a flame that was lit from a flame that has been burning since before Yom Kippur. Thus, one may ask permission from a neighbor to light a new flame from a flame they lit before Yom Kippur. One takes this new flame home and recites havdala over it (Ramban; Rema 624:5).
If one has no flame from before Yom Kippur and cannot light from such a flame he should not recite the berakha over fire after Yom Kippur (SA 624:4; BHL s.v. “ve-yesh omrim”). If Yom Kippur coincides with Shabbat, bedi’avad one may recite the berakha over a flame lit after Shabbat (MB 624:7; SHT ad loc. 9).
After havdala, we eat and drink joyfully, because it is still a somewhat festive time, and because it expresses our faith that God lovingly accepts those who return to Him. The Sages tell us that after Yom Kippur a heavenly voice proclaims, “Go, eat your bread in gladness, and drink your wine in joy; for your action was already approved by God” (Kohelet 9:7, Kohelet Rabba ad loc.; Rema 624:5).
Pious people and people of action show their alacrity by beginning to build their sukkot after Yom Kippur, thus going directly from one mitzva to the next (Maharil; Rema 624:5; Peninei Halakha: Sukkot 2:12).
Others say that we recite the berakha over spices after Yom Kippur that coincides with Shabbat, because the neshama yeteira is also expressed in an enhanced spirituality, which is now gone (Maharil; Avudraham). Others explain that we smell spices on Motza’ei Shabbat because that is when the wicked return to Gehinom, which causes a bad smell. Many authorities rule in practice that the berakha over spices is recited after Yom Kippur that coincides with Shabbat (Maharshal; Baḥ; Magen Avraham; Taz). However, if the halakha follows the view that there is no need to recite the berakha over spices, its recitation may constitute an unwarranted interruption (hefsek) during havdala (Ginat Veradim; Eliya Rabba; Maḥazik Berakha). Therefore, since the mitzva to make a berakha over spices is rabbinic, in cases of uncertainty it is not required, and therefore one should not interrupt the proper order of havdala for its sake. Thus, one who wishes to observe these halakhot most meticulously should recite the berakha over spices after completing havdala and drinking a bit of wine (Ru’aḥ Ḥayim 624:3).
. If Yom Kippur coincides with Shabbat, le–khathila one should make havdala using a flame that was lit before the holiday. This covers both reasons for the recitation of the berakha over fire – the one relevant to Shabbat and the one relevant to Yom Kippur (Ritva). Bedi’avad, the berakha may be recited even if only the Shabbat reason applies (SHT 624:9). However, if Yom Kippur is on a weekday, one may not recite the berakha over a flame lit after the holiday, nor a flame lit from another flame that was lit after the holiday, nor even on a flame lit by a non-Jew on Yom Kippur, because the berakha must be recited over a flame that was burning on Yom Kippur but forbidden to use. However, a flame that was lit on Yom Kippur on behalf of a dangerously ill person may be used for havdala after Yom Kippur; since it was permitted to light this flame, it has the status of “ner she-shavat” – a flame that was burning on Yom Kippur but not used for any forbidden melakha (SA 624:4-5).