The wisdom in sending a human messenger to human beings rather than an angelic one is this: His words, “your companion,” draw attention to Allah’s favor and kindness toward mankind, for He sent to them someone who lives among them, whom they may accompany and who accompanies them—a human like themselves. They are simply unable to receive revelation directly from an angel, as the Exalted says:

“They say, ‘Why has an angel not been sent down to him?’ Had We sent down an angel, the matter would have been settled at once and they would have been granted no respite. And had We appointed an angel, We would surely have made him appear as a man, thereby confusing them in the very thing about which they are now confused.” (Qur’an 6:8–9)

Ibn Abī Ḥātim reports—through Abū Zurʿah, Manjāb ibn al-Ḥārith, Bishr ibn ʿAmmārah, Abū Rawq, and al-Ḍaḥḥāk—from Ibn ʿAbbās that regarding the verse, “Had We sent down an angel, the matter would have been settled,” he said: “We would have destroyed them.” Concerning, “then they would have been granted no respite,” he said: “They would not have been given any delay.” And about, “Had We appointed an angel, We would surely have made him a man,” he explained: “If an angel were to come to them, he could only come in the likeness of a man, because they are incapable of gazing upon angels.” Other exegetes have said the same about, “and thereby We would have confused them”: We would have mixed matters for them and made them ambiguous, just as they confuse and obscure matters for themselves, until they fell into doubt and could not tell whether he was an angel or a human being.

Thus the Almighty has made clear that, were an angel to be sent, people could see him only in human form—exactly as Gabriel used to appear to the Prophet ﷺ when people saw him in the likeness of Dihyah al-Kalbī, or as a Bedouin when he came and questioned him about Islam, faith, and excellence. The same occurred when the angels visited Abraham and Lot and were seen by Sarah and Lot’s people: they came only in the guise of men. Likewise, when Gabriel came to Mary to breathe into her, he appeared to her as a man, as the Exalted says:

“She screened herself away from them, whereupon We sent to her Our Spirit, and he appeared before her as a well-proportioned man. She said, ‘I seek refuge with the Most Merciful from you, if you are truly God-fearing.’ He replied, ‘I am only a messenger from your Lord, sent to grant you a pure son.’” (Qur’an 19:17–19)

Since they cannot behold an angel except in the form of a man, had one come they would simply have said, “This is a human being, not an angel,” and the matter would have become confused and blurred for them. Their specious argument, therefore, would not have been removed merely by the descent of an angel.