והדרת פני זקן זה שקנה חכמה

The verse “And you shall honor the face of an elder” is read as a play on the word zaken, “elder”: zeh shekanah chochmah, “this one who has acquired wisdom.” The Alter Rebbe explains “acquired” through the phrase “those who hold the Torah”: a true scholar holds the Torah in his memory, engraved on his heart at all times, not only while he is studying.

The Talmud defines a Torah scholar as one who can answer a question of halachah wherever he is asked, which shows that his learning is always with him. For this reason the mitzvah to rise before him applies even when he is not studying at that moment.

The reason is that G‑d Himself dwells within such a scholar constantly, even while he attends to ordinary affairs, because the Torah engraved in his memory is one with G‑d. The Zohar cited here says that one rises before a Torah scholar because he embodies the holy form above.

From this the Alter Rebbe draws a lesson for anyone who longs to be bound to G‑d without a moment’s break. Since learning held in memory stays with a person even when he is not studying, the way to have G‑d dwell within him always is to “acquire” the Torah by committing it to memory.

Torah known by heart stays present even while a person attends to the body, in the “hidden world” of his soul, concealed from his active thought, where the yud of the Name Havayah shines. As is known in Kabbalah, the passage “Sanctify to Me every firstborn,” the first of the four passages in the tefillin, corresponds to the yud, Chochmah; this is why it speaks of “a remembrance between your eyes.”

The Laws of Torah Study, citing the Sifri, require every Jew to know the whole Torah: all 613 mitzvos with their fine details. The maamar gives the inner reason: the G‑dly soul has 613 powers, parallel to the 613 mitzvos, and knowing each mitzvah draws G‑d’s light onto its own power, so that no part of the soul is left without that light.

The verse “You are all beautiful, my beloved, and there is no blemish in you” stresses “all”: the soul is wholly beautiful only when every one of its powers receives G‑d’s light. For this reason the root of this light above is also made up of 613, matching the mitzvos and the powers of the soul.

This root of 613 is called “man,” as in Ezekiel’s vision of “a likeness like the appearance of a man” upon the throne. The sentence then makes a concession: the times are hard, people lack patience and breadth of mind, and the subject is deep.

Since few can master the whole Torah, a person should at least gather the strength to know by heart the Five Books of Moshe, which Moshe wrote as G‑d dictated. These books are the root from which the entire Torah, Written and Oral, grows.

That the whole Oral Torah is contained in the Written Torah is shown by the Talmud’s account of Rabbi Akiva, who would derive heaps upon heaps of laws from every crownlet on the letters. In the Five Books, however, these laws lie deeply concealed, at the level of the “hidden world.”

The Oral Torah, where the laws are spelled out, is the “revealed world,” and from it one should at least know the Order of Kodashim, the order of the Mishnah on the offerings and the Temple service. The Sages call this order “wisdom,” which fits the opening definition of an elder as one who “has acquired wisdom,” and the Arizal writes that it atones for sin; the parenthesis points to a discourse on Shir HaShirim that explains the verse further.