It is narrated from Hazrat Abu Huraira (may Allah be pleased with him) that once some people who hunted in the sea came to the service of the Holy Prophet (peace and blessings be upon him) and they asked the Holy Prophet (peace and blessings be upon him): "O Messenger of Allah (peace and blessings be upon him), we travel by sea and carry only a little water with us for drinking. If we use it for ablution, we will remain thirsty, and if we drink it, there will be no water left for ablution. Can we perform ablution with sea water?" The Holy Prophet (peace and blessings be upon him) replied: "The water of the sea is purifying and its dead (fish) is lawful."