وَقَالَا: لَا يَجُوزُ إِلَّا مِنْ عُذْرٍ.
Translation: Abu Yusuf and Muhammad said that this is not allowed except for an excuse.
This dispute specifically concerns a nafl begun while standing and then continued seated without excuse.
The two companions treat standing at commencement as an undertaking that cannot be discarded without reason during the prayer. Beginning a voluntary prayer while seated is a separate permitted case.
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Voluntary Prayers: Regular Sunnahs, Nawafil and Juristic Differences
وَقَالَا: لَا يَجُوزُ إِلَّا مِنْ عُذْرٍ.
Translation: Abu Yusuf and Muhammad said that this is not allowed except for an excuse.
This dispute specifically concerns a nafl begun while standing and then continued seated without excuse.
The two companions treat standing at commencement as an undertaking that cannot be discarded without reason during the prayer. Beginning a voluntary prayer while seated is a separate permitted case.