Mukhtasar Sahih Bukhari — Hadith 1860

Narrated by Abu Huraira (may Allah be pleased with him) from the Prophet Muhammad (peace be upon him) that he said: "It is not permissible for a woman to observe (voluntary) fasting when her husband is present except with his permission, nor should she allow anyone to enter his house without his consent. And if a woman spends (in the way of Allah) from her husband's wealth without his order, then he will get half of the reward."