I would like to propose a wonderful explanation for this matter based on the Midrash on this week’s parsha (S.R. 23, 6): "אז ישיר משה, הדא הוא דכתיב ואני אשיר עוזך וארנן לבוקר חסדך... ואני אשיר עוזך, אימתי, בשעה שעמדו ישראל על הים ואומרים שירה, שנאמר אז ישיר משה... וארנן לבוקר חסדך... אותו הבוקר של מתן תורה, שנאמר ויהי ביום השלישי בהיות הבוקר". “Then Moshe sang”: Regarding this it is written (Tehillim 59, 17): “I will sing of Your might, and I will rejoice toward morning in Your kindness” . . . “I will sing of Your might”: When did this occur? When Yisrael stood by the sea and were uttering words of song, as it is stated, “Then Moshe . . . sang.” . . . “And I will rejoice toward morning in Your kindness” . . . refers to that morning of Matan Torah, as it is stated (ibid. 19, 16): “On the third day when it was morning.” This Midrash teaches us that there is a fascinating connection between the “Shirah” uttered by Bnei Yisrael in relation to Krias Yam Suf and Matan Torah at Har Sinai. We will endeavor to explain this connection.
Let us refer to the following Gemara (Berachos 63b): "אמר ריש לקיש, מנין שאין דברי תורה מתקיימין אלא במי שממית עצמו עליה, שנאמר זאת התורה אדם כי ימות באהל". Reish Lakish said: From where do we learn that words of Torah are not retained except by one who sacrifices himself for her sake? For it is stated (Bamidbar 19, 14): “This is the Torah of a man who dies in a tent.” Simply understood, it is teaching us that a person should minimize physical pleasures. Here are the inspirational words of the Rambam on the subject (Hilchos Talmud Torah 3, 12):
The words of Torah will not be retained by a person who applies himself feebly to obtain them, and not by those who study amid pleasure and an abundance of food and drink. Rather, one must give up his life for them, constantly straining his body to the point of discomfort, without granting sleep to his eyes or slumber to his eyelids. The Sages alluded to this concept: “This is the Torah, a man should he die in a tent . . .” The Torah can only be retained by a person who gives up his life in the tents of the wise.
This in fact is the lesson taught by the Mishnah (Avos 6, 4): "כך היא דרכה של תורה פת במלח תאכל ומים במשורה תשתה, ועל הארץ תישן וחיי צער תחיה, ובתורה אתה עמל, ואם אתה עושה כן אשריך וטוב לך, אשריך בעולם הזה וטוב לך לעולם הבא". This is the way of the Torah: To eat bread with salt, to drink water in small amounts, to sleep upon the ground, to live a life of hardship, and to toil in the Torah. If you do so, you are praiseworthy, and it will bode you well. You will be praiseworthy in Olam HaZeh, and it will bode well for you in Olam HaBa. We find a similar elucidation in the Gemara (Sanhedrin 111a) related to a passuk extolling the virtues of the Torah (Iyov 28, 13): "לא ידע אנוש ערכה ולא תמצא בארץ החיים, לא תמצא תורה במי שמחיה עצמו עליה"—“Man does not know its true value, and it is not found in the land of the living” . . . the Torah is not found in someone who is self-indulgent.
The Turei Zahav: Denying Oneself to Engage in Torah Dialectic
We do, however, find an alternative interpretation of the statement: "שאין דברי תורה מתקיימין אלא במי שממית עצמו עליה". It is not referring exclusively to denying oneself physical pleasures but also to intellectual pursuits; one should devote oneself especially to studying Torah in depth and with “pilpul.” Here is a pertinent excerpt from the writings of the Turei Zahav (O.C. 47, 3):
"שהתורה אינה מתקיימת אלא במי שממית עצמו עליה, דהיינו שעוסק בפלפול ומשא ומתן של תורה, כמו שפירשו על [הפסוק] (ויקרא כו-ג) [אם] בחקותי תלכו, על מנת שתהיו עמלים בתורה, מה שאין כן באותם שלומדים דברי תורה מתוך עונג ואינם יגעים בה אין התורה מתקיימת אצלם".
Sacrificing oneself for the sake of the Torah means engaging in debates and “pilpul” regarding Torah issues; the study of Torah demands labor and exertion; it should not be a leisurely undertaking. Otherwise, the Torah one learns will not be retained.
Based on this understanding, the Turei Zahav explains the formula instituted by Chazal for the berachah related to Torah-study: "וצונו לעסוק בדברי תורה"—and He commanded us to engross ourselves in words of Torah. They did not employ the formula: "ללמוד דברי תורה". They were emphasizing the fact that the essence of the mitzvah of Torah-study is specifically the toil and exertion associated with it. Thus, they employed the term "לעסוק", from the root "עסק", indicating that we must actively engage in the study of Torah, debating points of ambiguity and disagreement. It is intellectual work that a person must treat like a business transaction.
