And he likewise transmits—with a sound chain—from Mujāhid regarding the Almighty’s words, “If You grant us a sound child,” that Mujāhid said: “They were afraid it might not be a human being.” The same meaning is reported from al-Ḥasan, Saʿīd, and others.
Biographical note: Ibn Ḥazm is the Andalusian scholar Abū Muḥammad ʿAlī b. Aḥmad b. Saʿīd b. Ḥazm al-Qurṭubī, the Ẓāhirī; d. 456 AH.
Relationship of this chapter to the Book of Tawḥīd: it clarifies that naming children—or anyone else—in a way that makes them “servants” of someone other than Allah constitutes associating partners with Him in obedience and is a denial of His favor.
Granted them: that is, Allah granted Adam and Eve the righteous child they had asked for.
A sound child: a well-formed offspring.
They attributed partners to Him: they made someone a partner with Allah in obedience.
In what He had granted them: i.e., in the child He bestowed on them, by naming him ʿAbd al-Ḥārith; no one should be called a servant except of Allah.
Exalted is Allah: He is far above that.
Above what they associate: i.e., above the polytheism practiced by the people of Mecca—the discourse shifts from specific persons to the general class.
They are unanimous: apparently he is citing a consensus.
On the prohibition of every name compounded with “servant of” for anyone other than Allah: because this constitutes shirk in Lordship and Divinity; all creatures belong to Allah and are His servants.
Except ʿAbd al-Muṭṭalib: they did not agree on prohibiting this particular name, either because its origin lay in literal slavery, or because it is simply the established proper name by which the man was known.