He may be answered as follows:

When you say, “If the expression were literal in the applications mentioned, it would be equivocal,” what do you mean by “equivocal”? If you mean equivocation in the strict sense—that an expression signifies two meanings without signifying any meaning common to them—some people dispute that this exists within a single language based on a single assignment of meanings. They say that it occurs only in two separate settings, as when one man gives his son a name and another gives his son that same name.

They do not say that giving heavenly bodies such names as Suhayl, al-Mushtarī, the Lion’s Heart, the Eagle, and the like involves a second assignment, whereby the Arabs and others who named them gave them transferred names, like transferred proper names—as when a man names his son Kalb (“dog”), Asad (“lion”), Namir (“leopard”), Bahr (“sea”), and so forth.

No reasonable person disputes equivocation in this sense. Yet it is clear that this is a second assignment. This is not altered by the way assigned proper names signify their referents, or by the distinguishing mark in figurative usage. In giving a name, one may intend the bearer to possess the quality it signifies: one may take its meaning as a good omen, seek to ward off the evil eye, name him after someone dear to oneself—a father, a teacher, or someone distinguished—or choose a name with a praiseworthy meaning, such as ‘Abd Allāh, ‘Abd al-Rahmān, Muhammad, or Ahmad.

In any event, this is a second assignment of the name to this bearer, and in this respect the expression becomes equivocal. Hence, with proper names, it is necessary to distinguish a person by his father’s name, or by his grandfather’s name together with his father’s if his own name and his father’s do not suffice to distinguish him. When these suffice, one confines oneself to them, as the Prophet did