The ruling on swimming and diving [while fasting]?
Shaykh Muqbil ibn Hādi al-Wādiʿī:
The importance is that nothing descends down his throat. Similarly, the [nature of] the sea differs.
If it is salt water, then it is possible that it will descend into the throat, and it is possible that if it isn’t salt water then it would not descend into the throat. As for the salt water, then I have swam in it and water enters the month bit by bit, then the water starts descending into the throat, the person tastes it and so on
So it descends down the throat, and due to this we advise to abstain from this. Similarly, if it isn’t salt water, it is also possible that it will descend down the throat, enter the stomach and break the fast.