נֻסח 'ספרד' says "אין כאלקינו" every day. On weekdays, it includes several paragraphs describing the makeup of the קטרת, followed by several פסוקים. On שבת, the description of the קטרת is cut ...
[Edit: According to Nusach Edot HamMizrach,] why does the Mussaf prayer on Shabbat and Rosh Chodesh include a description of the actual mussaf sacrifice, while the Mussaf prayer on Moed does not? Why ...
Why does the Shabbat Rosh Chodesh Musaf have its own special text (Ata Yatzarta Olamecha Mikedem ...) for the middle beracha?