Are married women allowed to fast religiously(vrata)?
There are countless verses in scriptures which counter this verse. Parashara Smriti is a Smriti text and Puranas are also Smriti text thus they have equal authority. Thus we can counter this verse by using Puranic verses as Authority.
Although there are countless counter verses in every Puranas. I have here used only Padma Purana.
Padma Purana Brahma Khanda chapter 5 states:
That woman who along with her husband, would observe a fast on the day of (i.e. sacred to) Vishnu, would have good sons and would be a favourite wife of her husband in every existence.
Similarly Padma Purana Shristi Khanda chapter 29 states:
Thus, for one year, a man or a woman or a maiden, having duly observed a fast at night and having devoutly worshipped Shiva for a year, should give a fully furnished bed at the end of the vow.
Similarly Padma Purana Shristi Khanda chapter 22 states:
If a man or a woman observes the vow of fast, (if) a pregnant woman or if a woman recently delivered, or a maiden or a sick woman observes fast at night (he or she would get unending fruit). When impure (i.e. during menstruation), she, being restrained, should get it done by someone else. He, who observes (the vow of) this Ananta-phalada (giving unending fruit) Trtijd, is honoured in Shiva's world for a full crore of Kalpas.
Thus as that verse of Parashara Smriti contradicts with so many other verses of Puranas and nor it is supported by Vedic verses, So it can be rejected.
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