The Talmud lists sleep as one-sixtieth of death, and also one-sixtieth of prophecy — positioning sleep as a liminal state between the mundane and the transcendent, with both physical and spiritual dimensions.
חֲמִשָּׁה וְשִׁשָּׁה וַעֲשָׂרָה סִימָן: חֲמִשָּׁה אֶחָד מִשִּׁשִּׁים, אֵלּוּ הֵן: אֵשׁ, דְּבַשׁ, וְשַׁבָּת, וְשֵׁינָה, וַחֲלוֹם. אֵשׁ — אֶחָד מִשִּׁשִּׁים לְגֵיהִנָּם. דְּבַשׁ — אֶחָד מִשִּׁשִּׁים לַמָּן. שַׁבָּת — אֶחָד מִשִּׁשִּׁים לָעוֹלָם הַבָּא. שֵׁינָה — אֶחָד מִשִּׁשִּׁים לַמִּיתָה. חֲלוֹם — אֶחָד מִשִּׁשִּׁים לַנְּבוּאָה. שִׁשָּׁה דְּבָרִים סִימָן יָפֶה לַחוֹלֶה, אֵלּוּ הֵן: עִטּוּשׁ, זֵיעָה, שִׁלְשׁוּל, קֶרִי, וְשֵׁינָה, וַחֲלוֹם. עִטּוּשׁ — דִּכְתִיב: ״עֲטִישׁוֹתָיו תָּהֵל אוֹר״. זֵיעָה — דִּכְתִיב: ״בְּזֵעַת אַפֶּיךָ תֹּאכַל לֶחֶם״. שִׁלְשׁוּל — דִּכְתִיב: ״מִהַר צֹעֶה לְהִפָּתֵחַ וְלֹא יָמוּת לַשַּׁחַת״. קֶרִי — דִּכְתִיב: ״יִרְאֶה זֶרַע יַאֲרִיךְ יָמִים״. שֵׁינָה — דִּכְתִיב: ״יָשַׁנְתִּי אָז יָנוּחַ לִי״. חֲלוֹם — דִּכְתִיב: ״וְתַחֲלִימֵנִי וְהַחֲיֵנִי״.
The numbers five, six, and ten are mnemonics for the categories to follow. The Gemara says: There are five matters in our world which are one-sixtieth of their most extreme manifestations. They are: Fire, honey, Shabbat, sleep, and a dream. The Gemara elaborates: Our fire is one-sixtieth of the fire of Gehenna; honey is one-sixtieth of manna; Shabbat is one-sixtieth of the World-to-Come; sleep is one-sixtieth of death; and a dream is one-sixtieth of prophecy. Similarly: Six matters are good omens for the sick: Sneezing, sweating, diarrhea, a seminal emission, sleep, and a dream. These are all alluded to in Scripture: Sneezing, as it is written: “His sneezes flash forth light” (Job 41:10), indicating that by means of a sneeze one comes to see the light of the world. Sweat, as it is written: “In the sweat of your face shall you eat bread” (Genesis 3:19). Diarrhea, as it is written: “He that is bent down shall speedily be loosed; and he shall not go down dying into the pit” (Isaiah 51:14). A seminal emission, as it is written: “That he might see his seed, prolong his days” (Isaiah 53:10). Sleep, as it is written: “I should have slept; then had I been at rest” (Job 3:13). A dream, as it is written: “Wherefore You recover me [vataḥalimeni], and make me to live” (Isaiah 38:16); vataḥalimeni is interpreted as etymologically similar to ḥalom, dream.