I say: the specification of the relationship that occurs between the two related elements can only be a subject in meaning. Then, it may also be an agent in the technical sense, considering the original, thus being transformed from the genitive, like: "I admired Zayd's father's goodness," if the intention is to praise Zayd's father. It may not be so, and thus be suitable for the entrance of "min," like: "By Allāh, his excellence as a knight" and "Woe to him as a man," for "excellence" means goodness, and "woe" means destruction, and their attribution to the man is like the attribution of the verb to its agent, and the relation of the explanation to the word is the relation of the verb to the object, not to the agent. If you say: What is the reason for its accusative case? I say: It apparently is a circumstantial accusative based on the estimation of a genitive from the prepositional phrase and two genitives from the accusative. The original explanation is: the subject of the people of the language, then the two genitives were omitted as they were omitted in His saying: "So I took a handful from the messenger's trace" (Sūrah Ṭāhā, 20:96), meaning: the trace of the messenger's horse's hoof. And when the third was deputized for what is truly the circumstantial, it was obliged to be indefinite due to its deputation for what must be indefinite. And you may say: The original is the subject of the language, with the estimation of a single genitive, and the attribution of the subject to the language is metaphorical. This is the best of the interpretations, as some scholars have clarified, and it is the summary of what Ibn Hishām mentioned in his treatise on this issue, and whoever wishes to learn more about it should refer to it.