Lying on the left side means the right part of the body becomes accessible; it does not mean that only the left portion is washed. The objective is coverage of the entire body.
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Which area is washed in the left-side position?
Funerals: The Deathbed, Testimony, and Washing the Deceased
Lying on the left side means the right part of the body becomes accessible; it does not mean that only the left portion is washed. The objective is coverage of the entire body.