The Rebbe took his correspondence very seriously, personally responding to most letters addressed to him, even those sent by young children. Even letters that were ostensibly standard form letters – such as the congratulatory letters the Rebbe would send to weddings, bar and bat mitzvahs – were each reviewed and personally signed by the Rebbe, and many times he would add notes, amend the title of the recipient, or the like.
I'd like to share a letter from the Rebbe written to a youngster who informed the Rebbe about his upcoming bar mitzvah. What is unique about this letter is that it was written a week after the Rebbe suffered a massive heart attack on the holiday of Shemini Atzeret, 1977. For weeks following the heart attack, the Rebbe remained confined in his office-turned-hospital-room. It amazes me that, at this difficult time, the Rebbe took the time to address a small detail that the child wrote in his letter. Here is a free translation of the Rebbe's postscript to the standard bar mitzvah letter:
Regarding that which you write that "you stem from a secular family": certainly the "secular-ness" is an ancillary condition and an external "garment" that covers your essence and core. For every member of your family is the son of Abraham, Isaac and Jacob (and the daughter of Sarah, Rebecca, Rachel and Leah) and, following them, tens of generations of followers of Torah and its precepts.
Only that G‑d gave Man choice with regards to his actions, however, he cannot whatsoever change the essence, the core and his truest nature.
Below is the letter in its original Hebrew.
ב"ה, בדר"ח מ"ח, תשל"ח
ברוקלין, נ.י.
האברך . . . שי'
שלום וברכה!
במענה על הודעתו ע"ד הכנסו בקרוב לגיל מצות,
הנה יה"ר מהשי"ת אשר מבן שלש עשרה למצות יגדל לבן חמש עשרה וכו' כפסק המשנה (אבות פרק ה')
ויוסיף התמדה ושקידה בלימודו בתורה בתורת הנגלה וכן בתורת החסידות ויהדר בקיום המצות. והשי"ת יצליחו להיות חסיד ירא שמים ולמדן.
בברכה.
נ.ב. לכתבו אשר "מוצאו ממשפחה חילונית" – ודאי אשר "החילוניות" היא תופעת לוי ו"לבוש" חיצוני המכסה את העיקר והעצם הנמצא בו – שהרי כל אחד (ואחת) ממשפחתו שי' – בן אברהם יצחק ויעקב (ובת שרה רבקה רחל ולאה) ולאחריהם – עשיריות דורות שומרי תורה ומצות.
אלא שנתן השם הבחירה לאדם בנוגע להנהגתו, אבל אין כלל ביכולתו לשנות את העצם, העיקר והפנימיות שלו.