Kabbalah sa Isaias 33:6: Sha'arei Kedusha & Idra Zuta

Now, although it is true that about fear of HaShem-יהו״ה, blessed is He, the verse states,³⁵⁸Job 28:28 “The fear of HaShem-יהו״ה, that is wisdom,” and similarly,³⁵⁹Isaiah 33:6 “Fear of HaShem-יהו״ה, that is His treasure,” nevertheless, our sages, of blessed memory, stated,³⁶⁰Talmud Yerushalmi, Shabbat 1:3; Midrash Tanchuma BeHa’alotcha “What wisdom proclaimed to be the crown of its head, humility made into a heel (Eikev-עקב) for its sandal, as it states,³⁶¹Proverbs 22:4 – This verse is usually translated, “The result of humility is fear of HaShem-יהו"ה.” ‘The heel (Eikev-עקב) of humility is fear of HaShem-יהו״ה.’”

Rabbi Shimon said, I have not revealed everything in the Greater Gathering of Naso, and all these matters were hidden in my heart until now. I wanted to hide them for the world to come, since there in the world to come we are asked a question of wisdom, as said, “And he shall be the stability of your times, a store of salvation, wisdom and knowledge” (Yeshayahu 33:6), for they seek wisdom from him. He therefore withheld matters for the world to come. Now I see that the Holy One, blessed be He desires it, to reveal them, so I will enter without shame before his palaces.