A Festival cancels the seven-day and the thirty day periods of mourning. Thus, if one buries his dead before a Festival, and observed some time in mourning, as soon as the Festival begins, his mourning is suspended. Even if the burial took place on the eve of Yom Tov, toward the close of the day, so that the laws of mourning pertained to him, even if he merely removed his shoes for just a short time before Yom Tov, the Festival suspends the mourning, and we consider it as though he had observed the entire seven days of mourning. The first day of the Yom Tov is counted as the eighth day,¹ 548:22. and he then completes the thirty day mourning period. Even if the eve of Yom Tov is Shabbos, and he received timely news towards the evening, although on Shabbos the only laws of mourning observed are those concerning his private life, since at least these laws were observed, the Festival cancels the seven days of mourning.

footnotes: ¹ Although it is a Festival, since it is during the thirty days of mourning he may not wear freshly pressed garments. Ramban, Mishnah Berurah

If the mourner either inadvertently or intentionally neglected to observe any mourning² before the Festival, or if the burial took place close to nightfall, whereby he was unable to observe any mourning, the Festival does not cancel it, and he is subject to the same law as one who buries his dead during a Festival.

footnotes: ² If however he observed some aspect of mourning, the Festival does cancel the rest of the mourning (Sha’ar Hatzion 548:18).

If one of the days of mourning, except the seventh day, occurs on the eve of a Festival, since the Festival will cancel the seven-day mourning period, some Poskim permit him to wash his clothes, provided he does not wear them until nightfall. It is best to take care not to wash them until the afternoon,³ in the following paragraph says not to wash until near the evening. This is also the ruling of the Mishnah Berurah 548:37. so that it is evident that he is washing them on account of the Festival. He is forbidden to bathe until nightfall, but some Poskim permit bathing⁴ 548:39. after the Minchah service,⁵. Even then, he is permitted only near twilight. Yeshuos Yaakov, Mishnah Berurah 548:40. close to nightfall. In places where this custom prevails one may follow it. With regard to having his hair cut, all Poskim agree that it is forbidden.

footnotes: ³ The Kitzur Shulchan Aruch ⁴ Only bathing, but all other laws of mourning are observed until nightfall. Mishna Berurah ⁵ Only after he already prayed the Minchah service. Mogein Avraham

If he buried his dead seven days before the Festival, since he observed seven days of mourning before the Festival, the Festival cancels the thirty day mourning period. This is true even when the seventh day occurs on the day before Yom Tov; since we maintain that part of the day is like an entire day; as soon as the people leave the synagogue (in the morning), the seven day mourning period has been completed, and the remainder of the day is counted as part of the thirty-day mourning period, which is cancelled by the Festival. The mourner may wash his clothing, bathe, and have his hair cut on the eve of the Festival towards nightfall.⁶ 548. In case of emergency one can rely on the Shulchan Aruch and do these things in the afternoon. Mishnah Berurah 548:31. since he is doing it in honor of the Festival, and the Festival cancels the thirty-day mourning period. If the seventh day occurs on the eve of Pesach, since the afternoon which is the time the Pascal lamb was offered, is regarded somewhat as a Yom Tov, he is permitted to bathe immediately after midday and to have his hair cut before noon (since after midday, another person is forbidden to cut his hair for him).

footnotes: ⁶ Ramah

If the seventh day of mourning occurs on Friday, and Shabbos will be the eve of Yom Tov, he is permitted to wash his clothing, bathe, and have his hair cut on the eve of Shabbos.⁷ prayer. See Biur Halacha 548:8.

footnotes: ⁷ In this case he may do it even before he says the Minchah

If a mourner neglected to have his hair cut on the eve of Shabbos, or on the eve of Yom Tov, he is forbidden to have his hair cut on Chol Hamoed, since he was able to have his hair cut before then. He is, however, permitted to have his hair cut after Yom Tov. If the seventh day of mourning occurred on Shabbos, which is the eve of Yom Tov, since from the standpoint of the laws of mourning he was allowed to have his hair cut then, but was prevented because of Shabbos, it is considered as though he was prevented by an accident, and he is, therefore, permitted to have his hair cut even on Chol Hamoed.

A Festival cancels the thirty-day mourning period, only if the mourning is for other relatives; but if he is mourning for his father or mother, since he is forbidden to have his hair cut until his friends reprove him,⁸ 548:34. the Festival does not cancel this regulation.

footnotes: ⁸ If they reprove him, he is permitted on the thirtieth day of mourning. Mishnah Berurah

If one had observed mourning for one hour, (not exactly, but even less than an hour) before Pesach, that hour is considered like seven days, which together with the eight days of Pesach, make a total of fifteen days, to which he must add another fifteen days to complete the thirty-day mourning period. If he observed mourning for one hour before Shavuos, that hour is regarded as seven days, and the first day of Shavuos is also regarded as seven days (since its sacred offerings can be brought on any of the following seven days,) and the second day of Shavuos is counted as his fifteenth day, after which he must add another fifteen days. If he observed mourning for one hour before the Festival of Sukkos, it is counted as seven days, which together with the seven days of Sukkos make a total of fourteen days. The Festival of Shemini Atzeress is also counted as seven days (for it is a Festival in its own right, and amends⁹, too, counts as seven days. Mishnah Berurah 548:46. can be made for its sacrifices), making it a total of twenty-one days. The day of Simchas Torah counts as the twenty-second day, and he must add another eight days.

footnotes: ⁹ Amends actually cannot be made for its sacrifices, but since all the Festivals are compared to one another, Shemini Atzeress

Rosh Hashanah and Yom Kippur are also considered Festivals with regard to canceling the seven and thirty-day mourning periods. Thus, if one observed mourning for one hour before Rosh Hashanah, Rosh Hashanah cancels the seven day period, and Yom Kippur cancels the thirty-day period. If he observed mourning for one hour before Yom Kippur, Yom Kippur cancels the seven day period,¹⁰, he is permitted to wash in warm water that very day, because immersion in a mikvah on the day before Yom Kippur is a mitzvah. He is permitted to do so even though he usually does not do so on the day before a Festival. Since he must immerse in the mikveh the day before Yom Kippur, he is also permitted to bathe to remove any interposition. See Mishnah Berurah 606:23–27. The Mogein Avraham maintains in this case he should not bathe more than an hour or two before nightfall. If it is the last day of the seven days of mourning, he may bathe earlier (in the afternoon) Mishnah Berurah 548:24. and Sukkos cancels the thirty-day period.

footnotes: ¹⁰ If the burial took place the day before Yom Kippur

Although a Festival cancels the seven-day mourning period, nevertheless, the candle that is customarily lit in the place where the death occurred, to honor the soul of the deceased, should also be lit on Yom Tov. However, it is better to light it in the synagogue.