Expert in the secrets of the Law (Torah)/ erudite

Figuratively: well-versed in various and profound subjects of the Torah; a learned scholar thoroughly familiar with the material.

(“I am confident in you that you are well-versed in the inner chambers of the Torah, to expound by inference.” — Kiddushin 10b And likewise: “Rabbi Shimon the Temanite asked Rabbi Zeira: I have heard about you that you are well-versed in the chambers of the Torah, and I ask you one question. He said to him: How many years is the world? He said to him: Six thousand. He said to him: From where do you know this? He said to him: From the letters: alef, bet, gimel, dalet, heh, vav, zayin, het, tet, yod—these are fifty-five; kaf, lamed, mem, nun, samekh, ayin, peh, tsadi, kuf, resh, shin, tav—these are one thousand five hundred minus five. Return to the simple letters מנצפ״ך—these are three thousand…” — Recanati, Leviticus, chapter 25 And likewise: “Know that there are chambers of the Torah, and one who merits them—when he begins to innovate in Torah—enters the chambers, passing from chamber to chamber… and gathers treasures from there.” — Rabbi Nachman of Breslov, Likkutei Moharan, Teaching 245 And likewise: “Rabbi Yitzhak Shemalkish was well-versed in the chambers of the Torah… A man came to him and asked of him authorization to issue legal rulings.” — S. Y. Agnon, A Shroud of Stories, p. 223)

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