A theophany is a god’s appearance: Their visual representation in mortal eyes. One of the most well-known hallmarks of the ancient Egyptian pantheon is the prevalence of gods Who have animal aspects in Their images. Even to non-Kemetics—even to non-polytheists—the phrase “animal-headed god” brings to mind the variety of Kemetic gods sporting hawk and lioness faces, even though there are plenty of other deities in other pantheons and cultures that have powerful animal associations or forms.
It’s easy to assume that the Netjeru were considered in antiquity to be partially animals because of Their widespread animal theophanies, but this is not exactly the case. As gods, the Netjeru can take on any appearance They wish (even if They do often have preferences and thus more common appearances), but a theophany is just that: an appearance. Animal theophanies did not indicate that the Netjeru in question was that animal, but simply that the god could (and did!) use that animal’s appearance. A lioness-headed goddess could also be seen as fully human, or fully lioness, or perhaps even as a woman-headed lioness at times—theophanies were nearly a form of language in and of themselves, allowing humans to more fully understand the nature of the Netjeru. It could even help interpret a Netjeru’s “mood” or state of being: Hethert (Hathor) could be a dancing woman, a maternal wild cow, or a vengeful lioness, and while She always had the capacity for all three within Her, Her visual appearance could give a strong clue to which aspect(s) of Her were at the forefront.
In further example, a jackal Netjeru was not bound to the physical realities of a flesh-and-bone jackal, but instead wore the symbolism and mythology of the jackal like a suit: jackals were beautiful and swift creatures, but they also lived in the same areas where ancient Egyptians buried their dead, so jackal Netjeru were often associated with the dead and/or the process of embalming and preserving. The shriek of a kite was like the wail of a woman mourning, so Aset (Isis) and Nebt-het (Nephthys) were kites when They were wrought with grief over Wesir’s (Osiris’) death—or when They needed quick wings and long vision to find Wesir’s body.
Ancient Egyptian gods are rife with symbolism and rich in layered meanings; it’s important not to assume that a god with a particular theophany will only appear in that singular way, or that a god is chained to the physical realities of that animal if They do choose a theophany. I made that mistake myself when I laughed over the idea that Set could ever be seen as a spotted hyena, given all I know about hyenas and how mismatched their embodied qualities are with Set’s mythical attributes. Months later, I got a glimpse of how Set could, in fact, take a hyena as a theophany (which is a modern/theoretical theophany, by the way; it’s not historically-attested to my knowledge). From my personal journal:
Set-as-hyena, the one Who challenges and purifies. Set-as-hyena, the strength in the night, the sovereign, the bone-breaker, He Who removes corpses and the sickness they hold. Set-as-hyena, male but not hyena-masculine, the male that is too dominant to appease the females and stay with the clan, set off alone and powerful. Set-as-hyena, wearing a red pelt, male but built like a female and acting as one— which is masculine in other animals— so ungendered, genderfree, mixing male and female into His own particular blend of sex: yes, the shadow of the form of a spotted hyena.
In other words: think of theophanies like clothing that a god chooses to darn—not like a skin that a mortal is born with and cannot change.