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Public mourning does not take place on Shabbat because of its sanctity. Therefore, with the approach of Shabbat, the mourners wash in lukewarm water, dress in Shabbat clothes, and go to synagogue. They also eat Shabbat meals as usual, including singing Shabbat songs, as they would do on any other Shabbat. However, private mourning practices stay in effect even on Shabbat. Therefore, sexual relations are still forbidden, as are washing and applying lotion for pleasure. Shabbat does count as one of the days of shiva, as Shabbat is the soul of the week. Even when the week is one of mourning, the Shabbat within it is a part of it, and elevates the week through its sanctity.
Holidays cancel shiva. Even though they are less holy than Shabbat, the aspect of rejoicing on them is more outstanding. Therefore, if the mourners sat shiva even for an hour before the start of a holiday, the onset of the holiday ends the shiva. The holidays which have this power are those mentioned in the Torah: Passover, Shavuot, Rosh Ha-shana, Yom Kippur, and Sukkot. By contrast, the holidays instituted by the rabbis – Ĥanuka, Purim, and Israeli Independence Day –do not cancel mourning. If a funeral takes place on the intermediary days of a holiday, the shiva is delayed until the holiday is over, at which point the mourners observe the seven days of mourning.
