Why is Tisha B'Av treated differently than the other minor fasts in regard to pre-Shabbat postponement?

Fasts & MourningMinor Fasts

Synopsis

Tisha B'Av is not postponed before Shabbat (like Taanis Esther can be) because punishment and calamity are not advanced; they are only deferred when falling on Shabbat itself.

Late Acharonim
Lenient
Strict
Lesser cited
Major authority

Discussion

Discussion coming soon.

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