Reference for Pesachim 107:10

גן עדן דכתיב (בראשית ב, ח) ויטע ה' אלהים גן בעדן מקדם גיהנם דכתיב (ישעיהו ל, לג) כי ערוך מאתמול תפתה

Our fire [was created] at the termination of the Sabbath; the fire of the Gehenna, on the eve of the Sabbath. Yet was the fire of the Gehenna created on the eve of the Sabbath? Surely it was taught: Seven things were created before the world was created, and these are they: The Torah, repentance, the Garden of Eden, Gehenna, the Throne of Glory, the Temple, and the name of the Messiah. The Torah, for it is written, The Lord made me [sc. the Torah] as the beginning of his way.<span class="x" onmousemove="('comment',' Prov. VIII, 22.');">²⁶</span>

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