Is it permissible for a Muslim to make Ghusl for prayer using sea water when forced by necessity?
All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.
It is permissible for a Muslim to make Ghusl or perform ablution with sea water, even if he is not forced by necessity, because sea water is pure, i.e. it is pure by itself and purifies (what is washed by it). This goes back to the statement of the Prophet, sallallaahu ‘alayhi wa sallam, narrated on the authority of Abu Hurayrah : "It (the sea) is that of which the water is pure and dead ones (animals like fish) are lawful (to eat)." [Abu Daawood, An-Nasaa’i and Ibn Maajah]
Furthermore, water (in its general appellation) includes sea water and this is implied in the Statement of Allaah Almighty (which means): {…and do not find water, then seek clean earth and wipe over your faces and hands with it...}[Quran 5:6] Thus, whoever finds sea water might use it and there is nothing wrong with that.
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