knowledge of the Maker’s existence and the truthfulness of the Messenger.

The proofs of the Messenger’s truthfulness are numerous and have been discussed at length elsewhere.

On the basis of his prophethood, one can establish the details of Allah’s attributes and names, and His oneness—which means worshipping Him alone, without partner. This is His oneness in divinity. Likewise, one can establish His oneness in lordship.

Both forms of divine oneness can thus be known through revelation. More than one accomplished practitioner of rational inquiry has acknowledged this, stating that the Messenger’s truthfulness can be known before divine oneness is known. Yet by “knowledge of divine oneness,” al-Khattābī meant—and Allah knows best—knowledge of the Lord’s attributes and names, glorified is He, for they call this “knowledge of divine oneness.” This can be known through revelation: the Maker’s existence is known in general terms through innate disposition and reason, whereas the details of His attributes and names are learned through revelation.

Furthermore, if it is known that genuine knowledge of divine matters is to be found with the prophets, peace be upon them—that they are truthful and acknowledged as such in what they report concerning these matters, and that this knowledge must be received from them—then the knowledge that these matters can be learned from the Messenger can be established through the same evidence by which he is known to be a messenger. Once he is known to be a messenger, one learns this from him