Halachah 1 — Cooking and Its Measure
One is liable for cooking when preparing even a small amount, defined as the size of a dried fig. The Rambam clarifies that baking, cooking, boiling herbs, and heating water are all considered the same category of labor.
The minimum measure depends on the substance:
- For water: enough to wash a small limb
- For herbs: enough for their intended use
This shows that the definition of cooking depends on functional usefulness, not just raw quantity.
Halachah 2 — Cooking Through Heat Sources
Cooking is not limited to direct fire. One who cooks using a derivative of fire (such as heat transferred from a vessel) is also liable.
For example:
- placing an egg near a hot vessel until it cooks,
- softening certain foods with hot water.
In these cases, the final stage of preparation is considered cooking, and one is therefore liable.
Halachah 3 — Heat of the Sun vs. Fire
A fundamental distinction is made between:
- heat derived from fire, and
- heat derived from the sun.
Cooking using direct sunlight or its derivatives does not carry full liability, since it is not the normal way of cooking. However, the Sages prohibited such activity to prevent confusion with actual cooking.
Additionally:
- cooking fully cooked food → exempt
- cooking food that requires no cooking → exempt
The prohibition applies only where cooking is meaningful.
Halachah 4 — Participation in Cooking
When multiple people contribute to cooking, each may be liable if their action is essential to the process.
If all necessary components are added in sequence (fire, pot, water, food, spices, stirring), each contributor participates in the act of cooking.
However, if the fire is added only afterward, liability falls primarily on:
- the one who added the fire,
- and the one who stirred.
This highlights that cooking is defined by activating the process, not merely assembling ingredients.
Halachah 5 — Roasting and Baking Thresholds
Cooking is defined not only by complete cooking, but also by partial preparation.
For example:
- if a portion the size of a dried fig is fully cooked → liable
- if the entire item is half-cooked on both sides → liable
Even if cooking is incomplete, reaching a certain stage creates liability.
A person who begins baking accidentally may remove the item before completion to avoid liability.
Halachah 6 — Heating Non-Food Substances
Cooking is not limited to food.
One is liable for:
- melting metal,
- softening or hardening substances,
- heating clay until it becomes firm,
- melting wax or similar substances.
The general principle is:
Any transformation caused by heat—whether softening or hardening—is considered cooking.
Halachah 7 — Shearing (Cutting Hair or Fibers)
Removing wool or hair from animals is the labor of shearing, whether the animal is alive or dead.
Even removing feathers from a bird is included.
The minimum measure is the quantity needed to spin a thread of a specified length.
However, extracting fibers in an unusual way (such as spinning directly from a living animal) is exempt because it is not the normal method.
Halachah 8 — Cutting Hair and Nails
Cutting one’s:
- hair,
- nails,
- beard,
is a derivative of shearing and is liable when done with a utensil.
If done by hand, one is exempt.
Removing warts is generally exempt, unless done in specific Temple contexts for ritual service.
Halachah 9 — Minimum Measures and Special Cases
For hair removal:
- liability begins with removing two hairs
- removing a single white hair from dark hairs is also liable
The Rambam also discusses partial tearing or peeling of nails or skin and distinguishes between:
- cases that cause discomfort (some leniency),
- and those that do not (stricter prohibition).
Halachah 10–11 — Whitening and Laundering
Cleaning or whitening fabric is a prohibited labor.
This includes:
- washing garments,
- wringing out fabric.
Wringing is considered part of the laundering process, just as stirring is part of cooking.
However:
- wringing hair is not included,
- wringing leather is not included.
Halachah 12 — Beating Fibers
Processing fibers through beating or softening them into usable thread material is a distinct labor.
This applies to:
- wool,
- linen,
- sinews.
The measure is tied to the amount needed for spinning thread.
Halachah 13–14 — Dyeing and Creating Color
Dyeing requires a lasting change in color.
Temporary coloring does not incur liability.
Creating dye itself (by mixing substances that produce color) is considered a derivative of dyeing.
The minimum measure is the amount needed to dye a thread of a specified length.
Halachah 15 — Spinning
Spinning fibers into thread is a primary textile labor.
This includes fibers such as:
- wool,
- flax,
- animal hair,
- sinews.
Producing felt is considered a derivative of spinning when it creates a usable material.
Halachah 16 — Making Heddles and Frameworks
Constructing elements used for weaving, such as heddles or frames, is a distinct category.
Even making small structural elements used in weaving or similar crafts can incur liability.
Halachah 17–18 — Mounting the Warp and Weaving
The preparation of threads (warp) and the weaving process itself are distinct labors.
Actions include:
- aligning threads,
- stretching them,
- inserting weft threads.
Liability arises for even small completed sections or for finishing a garment.
Halachah 19 — Derivatives of Weaving
Activities resembling weaving include:
- separating threads,
- braiding hair.
These are considered derivatives because they form intertwined structures.
Halachah 20 — Undoing Fabric (Tearing Constructively)
Undoing or tearing fabric is only prohibited when done constructively, such as:
- preparing material for repair,
- improving a garment.
Destructive tearing is not included in the same way.
The measure aligns with the minimum required for meaningful repair.
Core Principle of the Chapter
This chapter demonstrates that the prohibition of labor on Shabbat extends beyond obvious acts like cooking or weaving.
Instead, the law focuses on:
Any act that transforms materials—through heat, cutting, combining, or structuring—when done in a meaningful and constructive way.