A Christian woman who is married to a Muslim man made a vow that if she gave birth to a boy, she would fast Ramadhaan five times (i.e. observe fasting on Ramadhaan for five years). Later on, she embraced Islam and wanted to fulfill her vow, but she cannot make up for all these fasts. What is the religious ruling in this regard? What should she do? What is the ruling if a person vows to do something that is already obligatory under the Sharee‘ah?
All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.
When a person makes a vow to do an act that is already obligatory on him such as fasting or prayer, such a vow is invalid and is not considered a binding vow according to Muslim jurists. This is because a vow is committing oneself to do a particular thing and one cannot commit himself to what is already obligatory on him. These acts are mandatory by virtue of the Islamic Sharee‘ah and vowing to perform them is meaningless and no expiation is due then, according to the correct opinion of Muslim scholars. This is also the adopted opinion of the Shaafi‘i school of Fiqh as stated by the author of Al-Muhath-thab and the majority of the Shaafi‘i scholars. This is also the adopted opinion of the Hanbali scholars, and others.
Hence, this woman is not required to do anything in this regard.
Allaah Knows best.
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