Does one incur an obligation to fast if the fast was accepted only by mental intention outside of the prescribed time, without formal verbal acceptance?

Fasts & MourningFast Acceptance

Synopsis

Authorities dispute whether mental intention alone (without afternoon prayer acceptance) creates a binding obligation to fast, with some treating it as a vow.

Late Acharonim
Lenient
Strict
Lesser cited
Major authority

Discussion

Discussion coming soon.

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