Q. Is it true that in Yiddish the day after Yom Kippur is called Tzu Gotts Nomen (“In God’s Name”)?
A. This custom, not widely followed, reflects the fact that during the Ten Days of Penitence the third paragraph of the Amidah concludes, HaMelech HaKadosh (“Holy King”) instead of the usual HaE-l HaKadosh (“Holy God”).
The reference to God as King is characteristic of this time of the year when the Creator, by bringing the world into being, acquired a realm over which to rule as King.
Once Yom Kippur has ended, we resume the normal phrase, “Holy God”. This led to the custom of calling the next day Tzu Gotts Nomen, the day when we return to God’s Name.