Welcome to Embrace Shabbat. In his sefer Yaarot Dvash (Volume 1, Essay 319) , Rav Yonatan Eybuschutz quotes the well-known concept that gehenom turns off on Shabbat. One of the reasons why we smell besamim - fragrances- on Motzai Shabbat is because our soul is sensitive to the stench that comes from the rekindling of the furnaces of gehenom . To offset that negative stench, we smell besamim. Our Rabbis also teach that those who keep Shabbat during their lifetime are given a respite from gehenom on Shabbat. However, this only applies to those who keep Shabbat. Additionally, the longer one keeps Shabbat, the longer this period of respite. For example, one who keeps an additional 72 minutes of Shabbat after nightfall will receive an corresponding 72 minutes of additional respite in the next world. The same is true in accepting Shabbat; if one takes in Shabbat early, it’s impact is also transferred to the next world. The question then arises as to why we must smell besamim on Motzai Shabbat if, seemingly, the fires of gehenom do not turn off completely due to the mechalelei Shabbat who do not have respite in the next world. The Yearot Devash explains that there are other gehenoms, aside from the gehenom of fire. There is also the cold gehenom sheleg , the gehenom of snow. The Vilna Gaon teaches that gehenom is created from a person’s actions. If a person ignites the fires of desire and anger in this world, they create a similarly heated gehenom in the Next World. However, if a person does mitzvot, but is cold and lazy in his performance, his lack of fiery passion creates a gehenom of snow in the Next World. Those who don’t keep Shabbat in this world switch from the fires of gehenom to the gehenom of snow on Shabbat in the Next World. Observance of Shabbat protects a person from both forms of gehenom because of the aspects of shamor and zachur. Zachur refers to all of the positive aspects of Shabbat, whereas shamor refers to all of the actions we refrain from on Shabbat. Because of these two components, Shabbat has the power to protect a person from both gehenoms and purify them. Even if a person sins with Avodah Zara, the worst possible sin, Shabbat forgives, atones, and purifies.