823. The dress which a person uses for offering prayers should be Mubah. Hence, if a person knows that it is Haraam to use a usurped dress, and intentionally offers
prayers with the usurped dress, or a dress in which usurped thread or button or anything else is used, his prayers would be void.
824. If a person knows that it is Haraam to wear usurped dress, but does not know that it makes prayers void, and if he intentionally offers prayers with usurped dress, his prayers will be void.
825. If a person does not know that his dress is usurped, or forgets about it being usurped, and offers prayers with it, his prayers is in order, provided that he himself is not the usurper. But, if he himself is the usurper, and forgets about it being usurped, and offers prayers with it, his Namaz, as per obligatory precaution, will be void.
826. If a person does not know or forgets that his dress is a usurped one, and realizes it during prayers, he should take off that dress, provided that his private parts are covered by another thing, and he can take off the usurped dress immediately without the continuity of the prayers being broken, his prayer is in order. But, if he himself is the usurper, and forgets about it being usurped, his Namaz as mentioned earlier, as per obligatory precaution, will be void.
And if his private parts are not covered by something else, or he cannot take off the usurped dress immediately, or the continuity of the prayers is not maintained if he takes if off, and if he has time for at least one Rak’at, he should abandon the prayers and offer prayers with a dress which has not been usurped. But if he does not have so much time, he should take off the dress while praying, and complete the prayers according to the rules applicable to the prayers by the naked.
827. If a person offers prayers with a usurped dress to safeguard his life or, for example, to save the dress from being stolen by a thief, his prayers are in order.
828. If a person purchases a dress with the particular sum of money whose Khums or Zakat has not been paid by him, and while offering the prayer he is aware of that, his prayers will be void. However, if he is not aware while offering the prayers, his prayers will be in order. If one’s unawareness is due to ignorance of not knowing the ruling, as per obligatory precaution, he should repeat the prayers.