His statement, “and breathe outside the vessel,” means that breathing into the vessel is disliked. Thus, if a person has little breath and cannot refrain from breathing, but wishes to take a breath, he should move the vessel away from his mouth and then breathe.

His statement, “and drinking from the mouth of a waterskin is disliked,” is because the Prophet, peace and blessings be upon him, forbade this (1), and because the waterskin may contain harmful things of which one is unaware. If the water is poured into a vessel, one can inspect it to see whether it contains anything harmful. Among such harmful things is the leech: a red worm that feeds on water. If a person drinks water containing a leech and it enters his body, it may sometimes attach itself to the wall of the esophagus, or to what precedes it; at other times, it descends into the stomach, attaches itself there, bites, and feeds from it. It then grows and swells until it completely obstructs breathing. For this reason, people may sometimes perish because of it.

His statement, “and during one’s meal, if it is not habitual,” means that drinking during a meal is disliked if it is not a person’s habit. If a person is accustomed to doing so, there is nothing wrong with it. Some also said that drinking immediately after a meal, if it is not habitual, is disliked.

The phrase, “if it is not habitual,” indicates that the matter is based on medical considerations. They said that drinking during a meal spoils the food and removes its benefit; the same applies if one drinks immediately afterward. But if a person is accustomed to this, it does not harm him.