Is it permissible for a man to wash a non-mahram woman, or for a woman to wash a non-mahram man?

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The washing of a woman by any man, or a man by any woman, is prohibited, even if they are closely related by blood relation (mahram). This is the position held by the majority of scholars. The reasoning is that such relatives are prohibited in life, therefore their washing after death is not permitted, similar to a non-related person (ajnabiyyah) or a foster sister. Ahmad found the notion of a man washing his daughter objectionable, citing the principle of seeking permission before entering upon one's mother while she is alive.