A wife's vow to fast
3-8-2015 | IslamWeb
Question:
I checked almost all the fatwas on the expiation for abortion. Ten years ago, I aborted a two-and-a-half month old fetus due to my husband's persistence and intense pressure. I ask Allah to forgive both of us. Having done so, I made a vow to Allah to fast two consecutive months. I indeed started fasting a week ago, but my husband objected, and he is looking for an alternative for the expiation. His opinion is that seeking the forgiveness of Allah and not repeating this action are enough to expiate for our sin. Would you please advise. Should I resume the vowed fast against my husband's will so as to fulfill the vow?
Answer:
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.
If pregnancy does not constitute a real threat to the mother's life, which can only be proved based on a report from a trustworthy and reliable doctor, then what your husband and you did concerning having an abortion is prohibited. It is impermissible for him to command you to do this and you are not allowed to obey him. No obedience is due for a creature concerning something that involves disobedience to the Creator. Since this has already happened without a Sharee'ah-approved excuse, you are required to repent to Allaah Almighty and ask for His pardon for killing an innocent human without legal claim.
Ghurrah (a young slave or bondmaid) or one tenth of the overall value of the mother's Diyah (blood money) is due when abortion takes place after a fetus has been formed. Some scholars also hold that, along with a Ghurrah or tenth of the Diyah, an expiation of fasting two consecutive months is obligatory. Others consider it recommended. This Ghurrah or Diyah is to be distributed among the inheritors of the fetus, excluding the perpetrator. This is the ruling on abortion.
A vow is not required for treating this mistake. If by the vow you meant the fast of the expiation, then the ruling has already been mentioned and you are not required to fast more than this. If you vowed to perform another fast against your husband's will, then he is entitled to prevent you (from doing this). This is so because you are not required to observe this fast by the Sharee'ah, but you made it obligatory on yourself without your husband's permission; so he is entitled to disallow you (from doing so).
The following is stated in Al-Mawsoo‘ah Al-Fiqhiyyah:
As regards the fast that a woman obliges herself to observe based on a vow, if she did so without her husband's permission, then the scholars unanimously agree that he is allowed to prevent her (from doing so). If she did so with his permission and specified a certain time for the fast, then he is not entitled to forbid her (from doing so). If she did not specify a certain time, then know that the Maliki scholars 
hold the opinion that he is entitled to forbid her (from doing so), unless she already started it. The Shafi‘i and Hanbali scholars provided two opinions in this regard.
Allaah Knows best.