(כח) וַיֹּ֘אמֶר֮ מֹשֶׁה֒ בְּזֹאת֙ תֵּֽדְע֔וּן כִּֽי־יהוה שְׁלָחַ֔נִי לַעֲשׂ֕וֹת אֵ֥ת כׇּל־הַֽמַּעֲשִׂ֖ים הָאֵ֑לֶּה כִּי־לֹ֖א מִלִּבִּֽי׃ (כט) אִם־כְּמ֤וֹת כׇּל־הָֽאָדָם֙ יְמֻת֣וּן אֵ֔לֶּה וּפְקֻדַּת֙ כׇּל־הָ֣אָדָ֔ם יִפָּקֵ֖ד עֲלֵיהֶ֑ם לֹ֥א יהוה שְׁלָחָֽנִי׃ (ל) וְאִם־בְּרִיאָ֞ה יִבְרָ֣א יהוה וּפָצְתָ֨ה הָאֲדָמָ֤ה אֶת־פִּ֙יהָ֙ וּבָלְעָ֤ה אֹתָם֙ וְאֶת־כׇּל־אֲשֶׁ֣ר לָהֶ֔ם וְיָרְד֥וּ חַיִּ֖ים שְׁאֹ֑לָה וִֽידַעְתֶּ֕ם כִּ֧י נִֽאֲצ֛וּ הָאֲנָשִׁ֥ים הָאֵ֖לֶּה אֶת־יהוה׃ (לא) וַיְהִי֙ כְּכַלֹּת֔וֹ לְדַבֵּ֕ר אֵ֥ת כׇּל־הַדְּבָרִ֖ים הָאֵ֑לֶּה וַתִּבָּקַ֥ע הָאֲדָמָ֖ה אֲשֶׁ֥ר תַּחְתֵּיהֶֽם׃ (לב) וַתִּפְתַּ֤ח הָאָ֙רֶץ֙ אֶת־פִּ֔יהָ וַתִּבְלַ֥ע אֹתָ֖ם וְאֶת־בָּתֵּיהֶ֑ם וְאֵ֤ת כׇּל־הָאָדָם֙ אֲשֶׁ֣ר לְקֹ֔רַח וְאֵ֖ת כׇּל־הָרְכֽוּשׁ׃ (לג) וַיֵּ֨רְד֜וּ הֵ֣ם וְכׇל־אֲשֶׁ֥ר לָהֶ֛ם חַיִּ֖ים שְׁאֹ֑לָה וַתְּכַ֤ס עֲלֵיהֶם֙ הָאָ֔רֶץ וַיֹּאבְד֖וּ מִתּ֥וֹךְ הַקָּהָֽל׃ (לד) וְכׇל־יִשְׂרָאֵ֗ל אֲשֶׁ֛ר סְבִיבֹתֵיהֶ֖ם נָ֣סוּ לְקֹלָ֑ם כִּ֣י אָֽמְר֔וּ פֶּן־תִּבְלָעֵ֖נוּ הָאָֽרֶץ׃
(28) And Moses said, “By this you shall know that it was Adonai who sent me to do all these things; that they are not of my own devising: (29) if these people’s death is that of all humankind, if their lot is humankind’s common fate, it was not Adonai who sent me. (30) But if Adonai brings about something unheard-of, so that the ground opens its mouth and swallows them up with all that belongs to them, and they go down alive into Sheol, you shall know that those involved have spurned Adonai.” (31) Scarcely had he finished speaking all these words when the ground under them burst asunder, (32) and the earth opened its mouth and swallowed them up with their households, all Korah’s people and all their possessions. (33) They went down alive into Sheol, with all that belonged to them; the earth closed over them and they vanished from the midst of the congregation. (34) All Israel around them fled at their shrieks, for they said, “The earth might swallow us!”
What is Sheol?
The Bible’s Sheol: An Underground Abyss by Rabbi Or N. Rose (https://www.myjewishlearning.com/article/heaven-and-hell-in-jewish-tradition/)
The subject of death is treated inconsistently in the Bible, though most often it suggests that physical death is the end of life. This is the case with such central figures as Abraham, Moses, and Miriam.
There are, however, several biblical references to a place called Sheol (cf. Numbers 30, 33). It is described as a region “dark and deep,” “the Pit,” and “the Land of Forgetfulness,” where human beings descend after death. The suggestion is that in the netherworld of Sheol, the deceased, although cut off from God and humankind, live on in some shadowy state of existence.
While this vision of Sheol is rather bleak (setting precedents for later Jewish and Christian ideas of an underground hell) there is generally no concept of judgment or reward and punishment attached to it. In fact, the more pessimistic books of the Bible, such as Ecclesiastes and Job, insist that all of the dead go down to Sheol, whether good or evil, rich or poor, slave or free man (Job 3:11-19).
Was Korach swallowed?
(9) The sons of Eliab were Nemuel, and Dathan and Abiram. These are the same Dathan and Abiram, chosen in the assembly, who agitated against Moses and Aaron as part of Korah’s band when they agitated against Adonai. (10) Whereupon the earth opened its mouth and swallowed them up with Korah—when that band died, when the fire consumed the two hundred and fifty men—and they became an example. (11) The sons of Korah, however, did not die.
And Rabbi Yoḥanan says: Korah was neither among the swallowed nor among the burned; he died in a plague. He was neither among the swallowed, as it is written: “And the earth opened its mouth and swallowed them and their houses and all the men who were with Korah” (Numbers 16:32), from which it is inferred: But not Korah himself. Nor was he among the burned, as it is written: “When the fire consumed two hundred and fifty men” (Numbers 26:10), but not Korah.
It was taught in a baraita: Korah was both among the burned and among the swallowed. He was among the swallowed, as it is written: “And the earth opened its mouth and swallowed them with Korah” (Numbers 26:10). He was among the burned, as it is written: “And fire came forth from the Lord, and devoured the two hundred and fifty men that burned the incense” (Numbers 16:35), and Korah was with them.
With regard to the verse: “And the sons of Korah did not die” (Numbers 26:11), it is taught in a baraita that in the name of our teacher, the Sages said: A place was fortified for them in Gehenna and they sat upon it and recited songs of praise. Rabba bar bar Ḥana said: One time I was walking on the path, and a certain Arab said to me: Come and I will show you those from the assembly of Korah who were swallowed. I went and I saw two fissures in the ground from which smoke was emerging. That Arab took a woolen fleece and dampened it with water and placed it on the tip of his spear and passed it over the fissures there. The fleece was singed, indicating the level of heat there. He said to me: Listen; what do you hear? And I heard that this is what they were saying: Moses and his Torah are truth, and they, referring to themselves, are liars.
What is Gehinnom?
Gehinnom: A Jewish Hell by Rabbi Or N. Rose (https://www.myjewishlearning.com/article/heaven-and-hell-in-jewish-tradition/)
Only truly righteous souls ascend directly to the Garden of Eden, say the sages. The average person descends to a place of punishment and/or purification, generally referred to as Gehinnom.
....Some view Gehinnom as a place of torture and punishment, fire and brimstone. Others imagine it less harshly, as a place where one reviews the actions of his/her life and repents for past misdeeds.
The soul’s sentence in Gehinnom is usually limited to a 12-month period of purgation before it takes its place in Olam Ha-Ba (see: Mishnah Eduyot 2:10 and Shabbat 33b). This 12-month limit is reflected in the yearlong mourning cycle and the recitation of the Kaddish (the memorial prayer for the dead).
Only the utterly wicked do not ascend to the Garden of Eden at the end of this year. Sources differ on what happens to these souls at the end of their initial time of purgation. Some say that the wicked are utterly destroyed and cease to exist, while others believe in eternal damnation (Maimonides, Mishneh Torah, Law of Repentance, 3:5-6).