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DAAT · LEVEL 1 — INTRODUCTION

Siman שמ"ט · 5 Seifim

The personal 4 amos in reshus harabim (a mobile private domain) — to discover and understand
סימן שמ"ט
דִּין אַרְבַּע אַמּוֹת בִּרְשׁוּת הָרַבִּים
🌱 Introductory Level · מתחילים
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A first approach to Siman שמ"ט: the full Hebrew text of the Mechaber, a clear translation, pedagogical explanations of the halachic concepts, modern practical cases, and a summary.

Topic: The personal 4 amos in reshus harabim (a mobile private domain)
Source: שולחן ערוך אורח חיים סימן שמ"ט (5 seifim)

Compilation: רב יוסף חיים סממה
DAAT · daattorah.com

📑 Study Outline

1. The text of the Shulchan Aruch — the 5 seifim of the Mechaber
2. The general context: why this siman, and what is the question?
3. The key halachic concepts of this siman
4. The seifim in detail — one by one
5. The Mishnah Berurah — first entries
6. The Rama's position — Ashkenazi vs. Sefardi differences
7. Modern practical cases
8. Practical summary and rules to remember
9. Comprehension questions

1. The text of the Shulchan Aruch

Siman שמ"ט contains 5 seifim of the Mechaber (Rabbi Yosef Karo) which codify the laws relating to the personal 4 amos in reshus harabim (a mobile private domain).

Seif א

דין ארבע אמות ברשות הרבים. ובו ה סעיפים:
כל אדם יש לו ארבע אמות ברשות הרבי' שיכול לטלטל בהם ומודדים לו באמה שלו ואם אמתו קטנה נותנים לו ארבע אמות בינוניות של כל אדם שכל אחת מהן ששה טפחים [וע"ל סי' שצ"ו]:
Translation: Every person has 4 amos in reshus harabim within which he may carry an object. They are measured by his own amah (forearm); and if his amah is small, he is given 4 average amos — each of 6 tefachim.

Seif ב

ארבע אמות שאמרו הן ואלכסונן שנמצ' שהם חמשה אמות ושלשה חומשין ויש מי שאומר שמארבע אמות עד חמשה ושלש חומשים פטור אבל אסור:
Translation: The 4 amos that were stated are reckoned together with their diagonal — which amounts to 5 amos and 3 fifths. And according to one opinion, from 4 amos up to 5 amos and 3 fifths one is patur aval assur (exempt but it remains forbidden).

Seif ג

מותר לו לאדם לעקור חפץ מרשות הרבים וליתנו לחבירו שאצלו בתוך ארבע אמותיו וחבירו לחבירו שאצלו אף על פי שהחפץ הולך כמה מילין ברשות הרבים ובלבד שלא יוציאנו חוץ מתחום שלו ויש מי שאוסר [ועיין לעיל סי' ש"א סעיף מ"ב]:
Translation: A person may lift an object from reshus harabim and hand it to his fellow next to him, within his 4 amos; and that fellow to his fellow next to him — even though the object travels several mil through reshus harabim — provided it is not taken out of his Shabbos techum. And according to one opinion this is forbidden.

Seif ד

היו שנים מקצת אמותיו של זה בתוך אמותיו של זה כגון שיש ביניהם ו' אמות מביאין ואוכלין באמצע ובלבד שלא יוציא כל אחד מתוך שלו לתוך של חבירו היו שלשה והאמצעי מובלע ביניהם כגון שבין שנים החיצוני' שמונה אמות האמצעי מותר עם כל א' מהחיצונים במה שארבע אמותיו מובלעים בתוך שלו ושנים החיצונים אסורים זה עם זה:
Translation: If there were two people, part of whose 4 amos overlap — for example, 6 amos between them — they may bring and eat in the middle [shared] area, provided neither takes an object out of his own area into his fellow's. If there were three, and the middle one is absorbed between them — for example, 8 amos between the two outer ones — the middle one is permitted with each of the outer ones in the part where his 4 amos overlap with theirs; but the two outer ones are forbidden with one another.

Seif ה

אסור להוליך חפץ פחות פחות מארבע אמות ואפי' בין השמשות ואפי' בכרמלית:
Translation: It is forbidden to move an object forward in successive segments of less than 4 amos [in order to circumvent the limit] — and this even during bein hashemashos, and even in a karmelis.
The complete text: these 5 seifim constitute the entirety of the Mechaber's codification on this topic. Each clarifies a case, a condition, or an exception.

2. The general context

What is this siman about?

Siman שמ"ט defines a particular space: the 4 amos that everyone possesses in reshus harabim. Carrying beyond 4 amos in reshus harabim is forbidden by the Torah (siman 346); but within these 4 amos, carrying is permitted. This siman clarifies the measurements and the cases in which several people's 4 amos overlap.

The fundamental question: the 4 amos are each person's "personal zone" in reshus harabim — the minimal space a person occupies to sit and stretch out. How are they measured? And what happens when the zones of two or three people overlap?

Place within Hilchos Shabbos

Siman שמ"ט continues the series on carrying. The Talmudic source is Eruvin 48a and Shabbos 96b — the verse "שְׁבוּ אִישׁ תַּחְתָּיו" (Shemos 16:29) teaches that everyone has the measure of his outstretched body: three amos, plus one to stretch out hands and feet.

3. The key halachic concepts

Four notions structure this siman:

The essential concepts of siman שמ"ט:

4. The seifim in detail — one by one

SeifContent
אEveryone has 4 amos in reshus harabim, measured by his own amah (at minimum 4 average amos of 6 tefachim).
בThe 4 amos "together with their diagonal" ≈ 5⅗ amos; between 4 and that figure: patur aval assur.
גOne may pass an object hand to hand, each within his 4 amos — even over several mil — without taking it out of the techum (one opinion forbids it).
דOverlapping zones: two people share the common zone; with three, the middle one is permitted with each, while the two outer ones are forbidden with one another.
הForbidden to move an object forward in segments of less than 4 amos — even at twilight, even in a karmelis.
The heart of the siman: the 4 amos are a personal zone. One may carry within it and even relay an object hand to hand from one zone to another — but one may not fraudulently cross the limit in small jumps, nor take an object out of its techum.

5. The Mishnah Berurah — first entries

The Mishnah Berurah of Rabbi Yisrael Meir HaKohen (the Chofetz Chaim) has 19 entries on this siman. Here are the first ones — to better understand the meaning of the seifim:

משנה ברורה (א) — (א) כל אדם יש לו וכו' - הטעם דכתיב שבו איש תחתיו והכונה ישיבת כל איש ביום השבת יהיה כשיעור תחתיו דהיינו כשיעור אורך כל גופו ושיערו חז"ל דאורך האדם שהוא שיעור תחתיו הוי ג' אמות ועוד אמה כדי לפשוט ידיו ורגליו ובשיעור זה יכול אדם לטלטל חפצים מכאן לכאן:
משנה ברורה (ב) — (ב) ארבע אמות - מצומצמות [מ"א] והיינו שימדוד אותן בצמצום ועיין בס"ב דארבע אמות שאמרו הן ואלכסונן:
משנה ברורה (ג) — (ג) באמה שלו - דהיינו אם האיש הזה הוא ארוך ביותר מודדין לו הד' אמות בזרוע שלו ונמצא שד' אמות שלו יהיו גדולין מד' אמות של שאר בני אדם:

For the full text of the 19 entries, see Sefaria: Mishnah Berurah 349.

6. The Rama's position

The Rama adds no gloss to this siman: the Mechaber and the Rama are unified. The Acharonim — Mishnah Berurah, Magen Avraham — clarify the measurement and the diagonal calculation.

The Acharonim's clarifications:

7. Modern practical cases

Siman שמ"ט applies whenever one must carry or pass an object in an unenclosed place:

SituationQuick analysis
Moving an object within a small radius in the streetPermitted within one's 4 amos; beyond that, forbidden (Torah prohibition in reshus harabim).
Passing an object hand to hand, each staying in placePermitted if each remains within his 4 amos and the object does not leave the techum (one opinion forbids it).
Two people sitting close to each otherThey share the overlap zone, without either encroaching on the other's zone.
Advancing an object "little by little" to cover a distanceForbidden — circumventing the 4-amos limit.
For precise practical cases: the exact measurement of the 4 amos and the overlap zones requires precision. For halacha lema'aseh, consult your Rav.

8. Practical summary of the Siman

The teachings of Siman שמ"ט:
  1. Everyone has 4 amos in reshus harabim — his personal carrying zone.
  2. Measurement: by one's own amah, but at minimum 4 average amos (6 tefachim each).
  3. Hand-to-hand relay permitted, each within his 4 amos, without taking the object out of the techum.
  4. Overlap zones: one shares the common zone without encroaching on one's own.
  5. Forbidden to advance an object in small segments of less than 4 amos.
  6. For halacha lema'aseh, consult your local Rav.

9. Comprehension questions

Check your understanding:
  1. What is the general topic of Siman שמ"ט?
  2. How many seifim does this siman contain? What is the theme of each?
  3. What is the difference between the Mechaber and the Rama (if any)?
  4. Which structuring halachic concepts appear in this siman?
  5. What is the practical takeaway for daily life?
  6. In which borderline cases must one consult a Rav?

To go further

If you want to delve deeper into this siman:
Continue the study — next simanSiman 350 →
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