DAAT · LEVEL 3 — MAGISTERIAL SYNTHESIS
Siman שס"ה
סימן שס"ה · דִּין מָבוֹי שֶׁנִּפְרַץ
Recap & mnemonics for review
📑 Synthesis plan
- The central axiom of the siman
- The condensed key concepts
- Hierarchy of pirtzah thresholds
- Decision tree — a breached mavoy
- Chatzer / mavoy asymmetry
- Mnemonic פֶּרֶץ
- Pitfalls to avoid
- Practical cases
- Final synthesis table
- The practical commandments
1. The central axiom
Siman שס"ה in one sentence.
A mavoy set up with a lechi or korah remains a closed domain in which one carries on Shabbos — so long as a pirtzah does not exceed the critical threshold and the tikun holds up. The whole siman measures: the width of the pirtzah (3, 4 or 10), its position (near the head or not), the passing of rabbim, and the fate of the mavoy when the lechi or korah falls.
A mavoy set up with a lechi or korah remains a closed domain in which one carries on Shabbos — so long as a pirtzah does not exceed the critical threshold and the tikun holds up. The whole siman measures: the width of the pirtzah (3, 4 or 10), its position (near the head or not), the passing of rabbim, and the fate of the mavoy when the lechi or korah falls.
2. The condensed key concepts
| Concept | Definition | Application |
|---|---|---|
| מָבוֹי | Alleyway closed on 3 sides | Domain of the siman |
| לֶחִי / קוֹרָה | Post / transverse beam | Tikun of the opening |
| פִּרְצָה | Breach in a wall | Thresholds: 3, 4 t. / 10 amos |
| פַּס ד' טְפָחִים | Remaining wall-pas of 4 t. | Preserves the mavoy's status |
| בָּקְעֵי בָּהּ רַבִּים | Rabbim pass through the pirtzah | Makes rule stricter (threshold → 4 t.) |
| לָבוּד | Gap less than 3 t. = joined | Pirtzah < 3 t. of no effect |
3. Hierarchy of pirtzah thresholds
Pirtzah of less than 3 tefachim → lavud "closes" it → of no effect, the mavoy remains mutar.
↓
Pirtzah of 4 tefachim to 10 amos → tolerated as a "pesach" (opening), provided a 4-t. pas remains at the head and rabbim do not pass.
↓
Pirtzah of more than 10 amos → no longer a pesach but a true pirtzah → the mavoy is asur, tikun is required.
4. Decision tree — a breached mavoy
Q1: Is the pirtzah less than 3 tefachim?
↓ YES → lavud, nothing to do; NO ↓
Q2: Is the pirtzah near the head (on the lechi/korah side)?
↓ YES → does a wall-pas of 4 t. remain? and pirtzah ≤ 10 amos? → mutar; NO ↓
Q3: Pirtzah in the middle of the side — do rabbim pass through?
↓ NO → tolerated up to 10 amos; YES → set up tikun already from 4 tefachim
→ At the slightest doubt → consult your Rav.
5. Chatzer / mavoy asymmetry
Seif ג teaches a counter-intuitive rule: when a mavoy is breached on its full width into a chatzer that did not make eruv with it —
| Domain | Verdict | Reason |
|---|---|---|
| The chatzer | Mutar | The mavoy does not "forbid" the chatzer; and the pirtzah of the mavoy does not strip the chatzer of its wall-returns (gippufin) |
| The mavoy | Asur | The chatzer, without eruv, "forbids" the mavoy — and the mavoy is breached on its full width onto a place asur to it |
6. Mnemonic פֶּרֶץ
פ — פַּס ד' טְפָחִים: a wall-pas of 4 tefachim at the head preserves the mavoy's status.
ר — רַבִּים בּוֹקְעִים: if rabbim pass through the pirtzah, the threshold drops from 10 amos to 4 tefachim.
ץ — צוּרַת הַתִּקּוּן: if the lechi or korah falls on Shabbos, carrying becomes asur from that moment (except in a walled city).
7. Pitfalls to avoid
Pitfall 1: Believing that every pirtzah forbids the mavoy. A pirtzah of less than 3 tefachim is of no effect (lavud); up to 10 amos it counts as a simple pesach.
Pitfall 2: Ignoring the passing of rabbim. The 10-amos threshold applies only if rabbim do not pass through; otherwise, one must set up tikun already from 4 tefachim (Rema, seif ב).
Pitfall 3: Confusing a pirtzah near the head with one in the middle of the side. Near the head, one also needs a remaining wall-pas of 4 tefachim (seif א).
Pitfall 4: Thinking that a tikun fallen on Shabbos remains valid by "shabbos kevan shehutra hutra". This leniency applies only to a walled city (seif ז).
8. Practical cases
| Situation | Analysis | Conduct |
|---|---|---|
| Communal-eruv pole torn down on Shabbos | Fall of tikun (seif ז) | Carrying asur from that moment, except in walled city |
| Gap of less than 3 tefachim in the fence | Lavud | Of no effect — the mavoy remains mutar |
| Pirtzah of more than 10 amos | True pirtzah | Tikun (tzuras hapesach) required |
| Rabbim use the pirtzah | Bokei rabbim (seif ב) | Set up tikun already from 4 tefachim |
9. Final synthesis table
| Element | Detail |
|---|---|
| Topic of the siman | Mavoy whose wall is breached or whose tikun falls |
| Place | Last siman of Hilchos Shabbos |
| Number of seifim | 8 (Mechaber) — 10 in the Shulchan Aruch HaRav |
| Talmudic source | מסכת עירובין — sugyos of the breached mavoy |
| Golden rule | Pirtzah: 3 t. (lavud) · up to 10 amos (pesach) · beyond (pirtzah). Rabbim passing lowers the threshold to 4 t. |
| Practical decision | Measure the pirtzah; check the eruv; consult your Rav |
10. The practical commandments of Siman שס"ה
For daily conduct
- Pirtzah of less than 3 tefachim: of no effect — lavud closes it.
- Pirtzah near the head: mutar if a wall-pas of 4 tefachim subsists and it does not exceed 10 amos.
- Pirtzah in the middle of the side: tolerated up to 10 amos — from 4 tefachim if rabbim pass through.
- Tikun fallen on Shabbos: carrying asur from that moment, except in a walled city.
- In case of doubt — consult your Rav; check the communal eruv each week.
- Deep pilpul — Level 2; Chabad shitah — Level 4.
📚 Recap of the study path
You have studied Siman שס"ה in 3 levels:
You have studied Siman שס"ה in 3 levels:
- 🌱 Level 1 — Base: the 8 seifim, English translation, halachic concepts
- ⚡ Level 2 — Lamdan: talmudic sources, שיטות of the Rishonim, מחלוקות, נפקא מינות
- ✨ Level 3 — Synthesis: axiom, mnemonic, decision tree, practical commandments