For the obligatory minimum, it is sufficient to move the water around in his mouth to the slightest extent, and to draw water into his nose until it enters the nostrils.

Being thorough is disliked for one who is fasting, because it may lead to swallowing the water or to its passing from the nose into the stomach. Hence, the Prophet ﷺ said to Laqit ibn Sabirah: “Perform ablution thoroughly, pass your fingers between the toes, and draw water deeply into the nose—unless you are fasting.” (1)

If a person has nasal sinuses such that, even if he draws water deeply into his nose, it becomes retained in these cavities and causes him pain, or becomes spoiled and leads to pus or the like, then we say to him in this case: Do not be thorough, in order to ward off harm from yourself.

Passing the fingers through a thick beard . . .

His statement, “Passing the fingers through a thick beard,” means that passing the fingers through a thick beard is among the sunnahs of ablution. A beard is either sparse or thick.

A sparse beard is one that does not conceal the skin. It and the skin beneath it must be washed, because what lies beneath it, being visible, is included in the face by which one faces another. A thick beard is one that conceals the skin. With it, only its outer surface must be washed. According to the well-known position of the madhhab, the hanging portion of it must also be washed.

It has also been said that this is not obligatory, just as wiping the portion of the hair that hangs below the head is not obligatory. (2) The view closer to what is correct is that it is obligatory. (3) The difference between it and the head is that, even if the beard grows long, it remains part of the face by which one faces another; thus it is included