If one was reciting Shema and excrement was within 4 amot when recitation began, must one return to the beginning?

PrayerShema

Synopsis

If excrement was within 4 amot from the outset — meaning the person was negligent in not checking — is the entire recitation invalid and must be repeated from the beginning?

Late Acharonim
Lenient
Strict
Lesser cited
Major authority

Discussion

Discussion coming soon.

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