---
title: Siman 549 – The 4 fasts
description: וChelek 6 1. From the words of the nevi’im there is an obligation to fast on the 9th of Av, on the 17th of Tammuz, on the 3rd of Tishray and on the 10th of Teves, because of the bad…
url: "https://mishnaberurasummaries.com/docs/siman-549-the-4-fasts/"
updated: "2026-07-27"
category: "Laws of Tisha B'Av"
---

# Siman 549 – The 4 fasts

וChelek 6

1. From the words of the nevi’im there is an obligation to fast on the 9th of Av, on the 17th of Tammuz, on the 3rd of Tishray and on the 10th of Teves, because of the bad things that occurred on them. (ShA  - MB )

1. The fasting is nothing more than a preparation for teshuva, therefore it is not proper to while away the fast engaged in outings and idle matters. (MB )

1. If you eat by mistake, still continue to complete the fast. (MB )

## Key

**ShA**
 : Shulchan Aruch

**MB**
 : Mishna Berura

**ShaH**
 : Shaar Hatsiun

**ShaT**
 : Shaaray Teshuva

**BeH**
 : Beur Halacha

**BaH**
 : Baer Haytayv

  [← PreviousSiman 548Mourning on C.H.](https://mishnaberurasummaries.com/docs/siman-548-mourning-on-c-h/)[Next →Siman 550Differences between Tisha B’Av and other fasts](https://mishnaberurasummaries.com/docs/siman-550-differences-between-tisha-bav/)

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