﴿ ۞ وَهُوَ ٱلَّذِى مَرَجَ ٱلْبَحْرَيْنِ هَٰذَا عَذْبٌۭ فُرَاتٌۭ وَهَٰذَا مِلْحٌ أُجَاجٌۭ وَجَعَلَ بَيْنَهُمَا بَرْزَخًۭا وَحِجْرًۭا مَّحْجُورًۭا ﴾

“AND HE it is who has given freedom of movement to the two great bodies of water – the one sweet and thirst-allaying, and the other salty and bitter - and yet has wrought between them a barrier and a forbidding ban.”

And He it is Who merged the two seas letting them flow one adjacent to the other this one palatable sweet and the other saltish bitter; and He set between the two an isthmus so that the one does not mix with the other and a forbidding ban a shield that prevents the two from becoming mixed.