unintentional. The person did not intend for the water to go down into his stomach; rather, he merely intended to moisten his mouth, but the water went down unintentionally.

A related question is whether it is permissible for a fasting person to use a toothbrush and toothpaste. The answer is that it is permissible, but it is preferable not to use them, because toothpaste readily penetrates and may go down the throat. Instead of doing so during the day, he should use them at night, or use the toothbrush without toothpaste.

Whoever eats while uncertain whether dawn has broken, his fast is valid. This is not so if he eats while uncertain whether the sun has set, or believing it to be night and it then becomes clear that it was daytime.

His statement, “Whoever eats while uncertain whether dawn has broken, his fast is valid,” means that whoever does something that invalidates the fast while uncertain whether dawn has broken, his fast is valid. This is because Allah, the Most High, says:

“Now lie with them and seek what Allah has decreed for you. Eat and drink until the white thread of dawn becomes distinct to you from the black thread [of night].” [al-Baqarah 2:187]

The opposite of certainty is doubt and conjecture. So long as dawn has not become clear to us, we may eat and drink, due to His saying, the Most High:

“Our Lord, do not take us to task if we forget or make a mistake.” [al-Baqarah 2:286]

This is a case of mistake.

It is also due to the hadith of Asma bint Abu Bakr—may Allah be pleased with her—who reported that they ate thinking that the sun had set, then it rose. (1) If this applies at the end of the day, then it applies all the more so at its beginning, because at the beginning one is permitted to eat and drink until dawn becomes clear to him.

This issue has five cases: