Sayyida Aisha (may Allah be pleased with her) says: The Messenger of Allah (peace and blessings be upon him) ordered Sahla bint Suhail (may Allah be pleased with her), when she was experiencing istihada (non-menstrual bleeding), to perform ghusl for every prayer. This was difficult for her, so the Prophet (peace and blessings be upon him) instructed her to perform one ghusl for Zuhr and Asr, one ghusl for Maghrib and Isha, and one ghusl for Fajr.
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