The source requires using whatever usable covering is actually available, even if borrowed/loaned for use. If ordinary clothing is unavailable, a man may use pure silk to cover the Awrah for prayer rather than pray naked; the necessity of covering takes priority in that situation. Other available materials that genuinely cover, such as grass or suitable mud in the classical examples, are also used when necessary.
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Use Any Lawful Available Covering
Awrah Exposure and Clothing Scarcity in Prayer
The source requires using whatever usable covering is actually available, even if borrowed/loaned for use. If ordinary clothing is unavailable, a man may use pure silk to cover the Awrah for prayer rather than pray naked; the necessity of covering takes priority in that situation. Other available materials that genuinely cover, such as grass or suitable mud in the classical examples, are also used when necessary.