DAAT · LEVEL 3 — MASTER SYNTHESIS
Siman שנ"א
סימן שנ"א · דִּין הַמּוֹשִׁיט יָדוֹ לְצִנּוּר בִּרְשׁוּת הָרַבִּים לִשְׁתּוֹת
Recap and mnemonics for review
📑 Synthesis outline
- The central axiom of the siman
- Key concepts condensed
- The status of the pipe
- Decision tree
- Catching in midair
- Mnemonic צִנּוֹר
- Pitfalls to avoid
- Practical cases
- Final summary table
- The practical commandments
1. The Central Axiom
Siman שנ"א in one sentence.
Collecting from the street the water of a roof gutter: permitted or forbidden? Everything depends on the status of the pipe. Stuck to the roof (within 3 tefachim), it is the roof — reshus hayachid. Protruding, narrow, low — it is mekom petur. Wide or high — reshus hayachid or out of reach. And catching water in midair escapes everything, because nothing has rested there.
Collecting from the street the water of a roof gutter: permitted or forbidden? Everything depends on the status of the pipe. Stuck to the roof (within 3 tefachim), it is the roof — reshus hayachid. Protruding, narrow, low — it is mekom petur. Wide or high — reshus hayachid or out of reach. And catching water in midair escapes everything, because nothing has rested there.
2. Key concepts condensed
| Concept | Definition | Application |
|---|---|---|
| מַזְחִילָה | Gutter along the roof | Stuck to the roof = reshus hayachid |
| לָבוּד | Less than 3 tefachim = "attached" | Attaches the gutter to the roof |
| קוֹלֵט מִן הָאֲוִיר | Catching water as it falls | No hanachah → permitted |
| ד' עַל ד' | Significant surface | 4×4 pipe = reshus hayachid |
| לְמַעְלָה מֵעֲשָׂרָה | Above 10 tefachim | Out of reach of reshus harabim |
3. The status of the pipe
Gutter within 3 tefachim of the roof → lavud → it is the roof → reshus hayachid → forbidden.
↓
Pipe protruding 3+ tefachim, without 4×4, below 10 → mekom petur → permitted.
↓
Pipe with 4×4 → reshus hayachid → forbidden. Pipe above 10 → forbidden.
4. Decision tree
Q1: Are you catching water in midair, before it reaches any surface?
↓ YES → permitted; otherwise ↓
Q2: Is the gutter within 3 tefachim of the roof?
↓ YES → forbidden (it is the roof); otherwise ↓
Q3: Does the protruding pipe have 4×4, or is it above 10 tefachim?
↓ YES → forbidden; NO ↓
→ Protruding pipe, narrow, low → mekom petur → permitted.
5. Catching in midair
| Situation | Ruling |
|---|---|
| Catching rainwater as it falls, before any surface | Permitted — nothing has rested |
| Collecting from a gutter stuck to the roof | Forbidden — transfer R"Y → R"R |
| Collecting directly from the wall | Forbidden (all the more so) |
| With the hand, the mouth, or a vessel | Same rule for all |
6. Mnemonic צִנּוֹר
צ — צָמוּד לַגַּג: gutter stuck to the roof (within 3 tefachim) = the roof = reshus hayachid → forbidden.
נ — נוֹפֵל בָּאֲוִיר: catching water as it falls midair → permitted, nothing has rested.
ו — וּבוֹלֵט קָטָן: protruding pipe, narrow (without 4×4), low (below 10) = mekom petur → permitted.
ר — רָחָב אוֹ גָּבוֹהַּ: wide pipe (4×4 = reshus hayachid) or high (above 10) → forbidden.
7. Pitfalls to avoid
Pitfall 1: Believing that a gutter, because it is at height, is not the roof. Within 3 tefachim, lavud makes it reshus hayachid.
Pitfall 2: Thinking that height (above 10) always permits. Here, even a protruding pipe above 10 is forbidden.
Pitfall 3: Believing only the hand is involved. The mouth and the vessel follow the same rule.
Pitfall 4: Confusing "catching in midair" with "collecting from a surface". Only water in free fall escapes the prohibition.
8. Practical cases
| Situation | Analysis | Conduct |
|---|---|---|
| Water from a gutter stuck to the roof | Lavud → reshus hayachid | Forbidden |
| Rainwater caught in free fall | No hanachah | Permitted |
| Narrow, low, protruding downspout | Mekom petur | Permitted |
| Wide pipe (4×4) or above 10 | Reshus hayachid / out of reach | Forbidden |
9. Final summary table
| Element | Detail |
|---|---|
| Subject of the siman | Collecting from the street the water of a roof gutter |
| Number of seifim | 1 |
| Mishnah Berurah | 10 entries |
| Talmudic source | עירובין צט ע"ב — מזחילה וצינור |
| Golden rule | Everything depends on the status of the pipe; catching in midair escapes everything |
| Practical decision | Identify the exact status of the pipe; consult your Rav |
10. The practical commandments of Siman שנ"א
For daily conduct
- Before collecting water from a roof, identify the status of the pipe.
- Gutter stuck to the roof: forbidden to collect water from it in the street.
- Catching in midair: permitted — nothing has rested.
- Protruding pipe, narrow, low: permitted; wide or high: forbidden.
- In case of doubt — consult your Rav.
- Deep pilpul — Level 2; Chabad shittah — Level 4.
📚 Recap of the study path
You have studied Siman שנ"א in 3 levels:
You have studied Siman שנ"א in 3 levels:
- 🌱 Level 1 — Base: the 1 seif, English translation, halachic concepts
- ⚡ Level 2 — Lamdan: Talmudic sources, shittos of the Rishonim, machlokos, nafka minos
- ✨ Level 3 — Synthesis: axiom, mnemonic, decision tree, practical commandments