On it being forbidden for a woman to fast voluntarily when her husband is present without his permission

Riyad as-Salihin (The Meadows of the Righteous)

by Imam Nawawi

336. Chapter: On it being forbidden for a woman to fast voluntarily when her husband is present without his permission

1750. Abu Hurayra stated that the Messenger of Allah, may Allah bless him and grant him peace, said, "It is not lawful for a woman to fast while her husband is present without his permission and she must not allow anyone to enter his house without his permission." [Agreed upon]