Are tzitzit strings valid if spun by a non-Jew while a Jew stands over him and instructs him to do it lishmah?

Synopsis

Rambam invalidates such strings because a non-Jew acts for his own purposes; the Rosh validates them when a Jew supervises. Ashkenazic custom adds that the Jew should assist a bit.

Rishonim
Early Acharonim
Late Acharonim
Lenient
Strict
Lesser cited
Major authority

Discussion

Discussion coming soon.

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