DAAT · LEVEL 3 — MASTER SYNTHESIS
Siman שנ"ז
סימן שנ"ז · דִּינֵי חָצֵר פָּחוֹת מֵאַרְבַּע אַמּוֹת וּבִיב
Summary & mnemonics for review
📑 Plan of the synthesis
1. The central axiom
Siman שנ"ז in one sentence.
Pouring out one's shofchin into one's own chatzer is, in itself, a permitted tiltul (reshus hayachid to reshus hayachid). But when the chatzer is too small to absorb the two se'in that a person uses each day, the water spills out into the public domain — and Chazal forbade it, as a gezeira lest one come to pour out directly into the reshus harabim. The whole thrust of the siman: either make the absorption possible (a gumma, the 4×4 amos shiur, a covered biv) or neutralize the problem (the rainy season, a karmelis).
Pouring out one's shofchin into one's own chatzer is, in itself, a permitted tiltul (reshus hayachid to reshus hayachid). But when the chatzer is too small to absorb the two se'in that a person uses each day, the water spills out into the public domain — and Chazal forbade it, as a gezeira lest one come to pour out directly into the reshus harabim. The whole thrust of the siman: either make the absorption possible (a gumma, the 4×4 amos shiur, a covered biv) or neutralize the problem (the rainy season, a karmelis).
2. The key concepts in brief
| Concept | Definition | Application |
|---|---|---|
| סָאתַיִם | Two se'in — one day's worth of shofchin | Baseline shiur of the siman |
| ד' אַמּוֹת עַל ד' | The area that absorbs two se'in | Threshold of a "sufficient" chatzer |
| גּוּמָא | A pit with the volume of two se'in | Remedy when the chatzer is too small |
| בִּיב | A covered drain running out to the street | Counts as a chatzer if covered for 4 amos, 4×4, of stones |
| רה"ר / כַּרְמְלִית | Reshus harabim / intermediate domain | The chumra applies only facing the reshus harabim |
3. Hierarchy of concepts
Principle: pouring from one's house into one's chatzer = reshus hayachid → reshus hayachid tiltul, permitted.
↓ exception
Problem: a chatzer of less than 4×4 amos, opening onto a reshus harabim, in summer — the water spills into the street: "as if he were pouring into the reshus harabim".
↓ remedies
Solutions: dig a gumma of two se'in; or have 4×4 amos (chatzer, combined surfaces, covered biv); or be in the rainy season; or border on a karmelis.
4. Decision tree — may one pour out?
Q1: Are we in the rainy season? → YES: permitted in every chatzer. NO ↓
↓
Q2: Does the chatzer border a karmelis (and not the reshus harabim)? → YES: permitted without a gumma. NO ↓
↓
Q3: Does the chatzer measure 4×4 amos (on its own, or by combining chatzer+achsadra / two adjacent levels)? → YES: permitted. NO ↓
↓
Q4: Has a gumma of two se'in been dug (covered with boards if it is outside)? → YES: permitted. NO → forbidden.
↓
→ Whenever in doubt → ask your Rav.
5. The gumma and the biv side by side
| Element | Gumma — seif א | Biv — seif ב |
|---|---|---|
| Function | Receives the shofchin when the chatzer is too small | Covered conduit that carries the water out to the street |
| Required shiur | Volume of two se'in (½ ama × ½ ama × ⅗ ama) | Covered for 4 amos, 4×4 amos wide |
| Absorption condition | Must hold two se'in; otherwise one pours nothing in at all | Absorbing stones — not a wooden conduit |
| If outside / in the street | Cover with boards → makom petur | The covered 4×4 are "chorei reshus hayachid" |
6. Mnemonic גּוּמָא
ג — גְּזֵרָה: the whole siman is a rabbinic gezeira — lest one come to pour out into the reshus harabim oneself.
ו — וְד' אַמּוֹת: a chatzer of 4×4 amos absorbs the two se'in; less than that, the water spills over.
מ — מַחֲזֶקֶת סָאתַיִם: the gumma must hold two se'in — short of that, one pours nothing in at all.
א — אֵין גְּזֵרָה: no gezeira in the rainy season, nor facing a karmelis.
7. Pitfalls to avoid
Pitfall 1: Thinking the issur applies all year. It only concerns the warm season, when the householder cares that the water drain away.
Pitfall 2: Thinking any gumma whatsoever suffices. If it does not hold the volume of two se'in, one pours nothing at all into it — an insufficient gumma is worse than none.
Pitfall 3: Forgetting to cover a gumma dug outside. Without boards it is not a makom petur (and may even become a karmelis).
Pitfall 4: Treating a biv as a chatzer without checking the material. A wooden conduit does not absorb water; one needs stones.
8. Practical cases
| Situation | Analysis | Conduct |
|---|---|---|
| Narrow patio opening on the street, in summer | The water spills over — "as if into the reshus harabim" | Forbidden without a gumma of two se'in |
| Same patio, in the rainy season | No gezeira — one does not insist on drainage | Permitted to pour out |
| Narrow chatzer + adjacent covered achsadra | The surfaces combine to 4×4 | Permitted to pour freely |
| Stone biv covered for 4 amos, 4×4 wide | Counts as a 4×4 chatzer | Permitted even at the mouth, even in summer |
| Chatzer opening on a karmelis | Kocho be-karmelis — no gezeira | Permitted without a gumma, even in summer |
9. Final synthesis table
| Element | Detail |
|---|---|
| Topic of the siman | Chatzer of less than 4 amos and biv — pouring shofchin on Shabbos |
| Number of seifim | 3 |
| Mishnah Berurah | 29 entries |
| Talmudic source | עירובין פח ע"א |
| Nature of the issur | Rabbinic — gezeira, lest one come to pour out into the reshus harabim |
| Golden rule | The issur only applies in summer, in a small chatzer opening onto the reshus harabim |
| Practical pesak | Measure the chatzer, identify the bordering domain, distinguish the seasons; ask your Rav |
10. The practical commandments of Siman שנ"ז
For daily conduct
- Rainy season: one pours freely in any chatzer.
- Summer, small chatzer opening on the street: forbidden without a gumma of two se'in.
- The gumma must hold the volume of two se'in; when dug outside, it must be covered with boards.
- Combined surfaces (chatzer + achsadra, adjacent levels) or a covered stone biv: each counts as a 4×4 chatzer.
- Chatzer bordering a karmelis: no gumma necessary, even in summer.
- When in doubt — ask your Rav. Pilpul: Level 2; Chabad shitta: Level 4.
📚 Summary of the learning path
You have learned Siman שנ"ז across 3 levels:
You have learned Siman שנ"ז across 3 levels:
- 🌱 Level 1 — Base: the 3 seifim, plain translation, halachic concepts
- ⚡ Level 2 — Lamdan: Talmudic sources, shittos of the Rishonim, machlokesin, nafka minos
- ✨ Level 3 — Synthesis: axiom, mnemonic, decision tree, practical commandments