The name "Shabbat HaGadol" – Ask the Rabbi
Q. Why is the Shabbat before Pesach called Shabbat HaGadol, “The Great Sabbath”?
A. The explanations include the following:
• Great (gadol) events happened in the lead-up to Pesach.
• The haftarah (from Malachi) refers to “the great and awesome (gadol v’nora) day of the Lord” (Mal. 3:22-24).
• In days when rabbis did not give regular sermons, the great scholar (gadol) of the community gave a discourse on that day, which made it “the Sabbath of the Great One”.
• Adding sections from the Haggadah to the afternoon service, and listening to the extensive discourse, made the day gadol (longer than usual).
• The name might originally have been Shabbat Haggadah, later corrupted to become Shabbat HaGadol.