Halachah 1 – The Types of Calamities That Require Public Fasts
The Rambam lists the communal disasters for which the public fasts and cries out to God:
- Enemy attacks
- War
- Plague
- Dangerous wild animals
- Locust infestations
- Crop blight and disease
- Building collapses
- Widespread illness
- Economic hardship and famine
- Harmful lack or excess of rain
These are considered communal crises requiring repentance, prayer, and fasting.
Halachah 2 – Who Fasts?
If a particular city suffers one of these calamities:
- That city fasts and sounds alarms.
- Neighboring cities fast but do not sound alarms.
- Neighboring communities pray for mercy on behalf of the afflicted city.
As a rule, public crying out is not done on Shabbat, except in special emergency cases.
Halachah 3 – Enemy Oppression
A communal fast is required when non-Jews:
- Wage war against Jews,
- Demand tribute,
- Seize territory,
- Attempt religious persecution,
even over a seemingly minor mitzvah.
The community fasts and prays until mercy is granted.
Halachah 4 – The Sword (War)
Even a war that does not directly involve Jews can be considered a public danger.
If foreign armies are fighting one another but pass through Jewish territory, the mere presence of war is a cause for fasting and prayer.
The Rambam derives this from:
“The sword shall not pass through your land.”
The sight of war itself is considered a calamity.
Halachah 5 – Defining a Plague
A plague (dever) is determined statistically.
For example:
- In a city of 500 working-age men,
- Three deaths on three consecutive days
constitute a plague.
Three deaths in one day or spread over four days do not.
Likewise:
- In a city of 1,000 people,
- Six deaths over three consecutive days
constitute a plague.
The same ratio applies to larger populations.
Halachah 6 – Spread of Disease
Women, children, and elderly people are not included in the population count used for defining a plague.
If plague strikes Eretz Yisrael:
- Jewish communities elsewhere also fast.
If frequent travel exists between two locations, both communities fast because the disease may spread.
Halachah 7 – Dangerous Wild Animals
A public fast is decreed only when a dangerous animal is considered “sent loose” among people.
Examples include:
- A predator appearing in a city during daylight.
- An animal that sees people and does not flee.
- An animal aggressively pursuing human beings.
These behaviors indicate abnormal danger.
Halachah 8 – Frontier Regions
In isolated wilderness areas where dangerous animals normally live, higher standards apply.
Simply seeing a predator is not enough.
However, if it enters homes and carries off a child, it is considered an extraordinary threat and fasting is instituted.
Halachah 9 – Snakes and Similar Creatures
For threats such as:
- Snakes
- Scorpions
- Other harmful creatures
the public cries out in prayer, but no public fast is decreed.
Halachah 10 – Locusts
Even a very small appearance of locusts in Eretz Yisrael is treated seriously.
The community fasts and sounds alarms over:
- Locusts
- Chasil (another destructive species)
- Gobai (a locust variety)
Ordinary grasshoppers require prayer but not a public fast.
Halachah 11 – Crop Disease
If blight or crop yellowing begins affecting produce, even in a small area, communal fasting and prayer begin immediately.
The Rambam stresses that agricultural damage is treated as a major public concern.
Halachah 12 – Building Collapse and Natural Disasters
When sturdy buildings begin collapsing unexpectedly, this is viewed as a communal calamity.
Likewise:
- Earthquakes
- Destructive winds
- Similar disasters
require fasting and public prayer.
Halachah 13 – Widespread Illness
If a particular disease spreads widely through a city and causes deaths, the community fasts and cries out.
Examples include:
- Epidemic illnesses
- Severe infectious conditions
The concern is not merely sickness, but sickness affecting many people.
Halachah 14 – Economic Depression
The Rambam also treats major economic collapse as a public crisis.
If commerce weakens so badly that merchants must sell goods far below value and still struggle to find buyers, the community cries out and seeks Divine mercy.
Economic suffering is considered a genuine public calamity.
Halachah 15 – Too Much Rain
Excessive rain can also be destructive.
If rainfall becomes so severe that homes collapse and people suffer, the community prays for relief.
However, in Eretz Yisrael such prayers are generally not offered because abundant rain is ordinarily a blessing and the terrain benefits from it.
Halachah 16 – Crops Drying for Lack of Rain
If crops begin growing and rainfall stops, causing vegetation to wither:
- The community fasts.
- The community prays.
This continues until sufficient rain falls or the season passes.
Similarly, if the fruit trees need rain around Pesach and it does not come, public fasts are instituted.
Halachah 17 – Water Shortages
When the rainy season arrives but reservoirs, wells, and cisterns remain insufficiently filled, fasting begins.
If drinking water itself becomes scarce, the community may fast and pray for rain at any time of year, even during the summer.
Halachah 18 – A Long Break in Rainfall
If rain stops for forty consecutive days during the rainy season, it is considered a severe drought.
The community fasts and cries out until rain returns or the season ends.
Chapter Theme
Chapter 2 defines the specific disasters that require communal fasting and prayer. The Rambam teaches that military threats, plague, agricultural destruction, dangerous animals, economic collapse, disease, building failures, and drought are all communal crises that demand not only practical action but also repentance, prayer, and collective spiritual response.