How should one accept the custom of fasting on Mondays and Thursdays - must one formally accept in advance?

HolidaysFasts & MourningMonday and Thursday Fasts

Synopsis

The fast should be accepted immediately when it becomes permissible (after the festival months), not delayed. Various authorities discuss whether saying 'Amen' to a public announcement, or formal acceptance in Mincha the day before, is necessary.

Early Acharonim
Late Acharonim
Lenient
Strict
Lesser cited
Major authority

Discussion

Discussion coming soon.

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