What is the ruling in regards to women wearing pants to pray in (without any prayer dress or Jilbab?
All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
If the pants are under other clothes; i.e., the pants are not the external dress, then you may perform the prayer wearing them.
But if there is no other dress covering the pants and the pants are so tight that the shape of the body is revealed in bowing, prostrating, etc., then, in this case, you should restrain from wearing such pants in general and especially at the time of praying.
The Muslim scholars do not agree that a woman may wear pants. The reason for their refusal is that pants reveal the beauties of the woman rather than covering it. In addition, wearing pants is an imitation of men which is forbidden in the Sharee’ah.
So, a woman should avoid wearing pants since the most important thing about a dress is covering the ‘Awrah while pants make the ‘Awrah more exposed.
However, if a woman wears it only to beautify herself for her husband, not intending to imitate men or non-Muslim women, then it is permissible.
For more benefit on women wearing pants (trousers), please refer to Fataawa 435553, 113595, 85748 and 88156.
Allah knows best.
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