Is tosefet Shabbat (adding from the mundane to the holy) a Biblical or Rabbinic obligation?

ShabbatTosefet Shabbat

Synopsis

The Mishnah Berurah (in the cross-referenced note at 261:19) rules that tosefet Shabbat is a Biblical positive commandment (mitzvas aseh m'deorayta), derived from Yom Kippur verses. The Gra and Rambam disagree.

Early Acharonim
Late Acharonim
Lenient
Strict
Lesser cited
Major authority

Discussion

Discussion coming soon.

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