As for what the Shaykh (Al-Mufid), may Allah سبحانه وتعالى support him, mentioned regarding the boundary of the face in ablution, which is defined as extending from the hairline to the bottom of the chin and between where the thumb and middle finger encircle, the reasoning behind this definition is as follows: What we have considered as part of the face is unanimously agreed upon to be so, while what exceeds this boundary is a matter of disagreement. Therefore, we adhered to what the ummah unanimously agreed upon and refrained from including what was disputed. No one has the right to claim that the face includes everything that faces forward because this would require including the ears, chest, and any other part of the body that faces forward, which is invalid without dispute. This reasoning is further supported by evidence.
Commentary #2