Is fasting on Rosh Chodesh forbidden, and what is the source of the prohibition — biblical or rabbinic?
Synopsis
Rosh Chodesh is universally prohibited for fasting, but authorities dispute whether the prohibition has a biblical basis or is rabbinic in origin.
More in Rosh Chodesh Prayers
May a congregation decree a public fast that falls on Rosh Chodesh, Chanukah, or Purim?
2 opinions
If a congregation began a multi-day fast series before Rosh Chodesh and Rosh Chodesh falls within those days, must they continue fasting on Rosh Chodesh itself?
5 opinions
If an individual accepted a private fast that falls on Rosh Chodesh — must he perform hatarat nedarim (annulment) to be released from it?
6 opinions across 3 eras
Does an oath (shevua) to fast on Rosh Chodesh take binding effect?
5 opinions across 3 eras
If someone fasts a taanis chalom (dream fast) on Rosh Chodesh, Chanukah, or Purim, must he observe a penitential fast afterward to atone for desecrating the day?
4 opinions
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