The powers of Opet are the triad from Karnak: Amun, Mut, and Khons. (The royal ka, also, but I talked about the royal ka in Conceptualising Opet.)
Amun, as the state deity of much of the New Kingdom, is here in His role as prime creator, and as father to the king and thus the one responsible for investing the royal ka in a material form. His name is "the hidden one" or "the secret one"; as god of secret power, He revealed Himself as Ra, whose realm is manifest, appearing power. The most etherial and transcendent of gods, Amun is a matter of holy presence and of breath (for He was also somewhat associated with the air, as the most etherial and transcendent of things). He is self-created, as are all the creator figures, and His animals include the goose ("The Great Cackler" is among His titles) and the ram (as a fertility symbol). At Opet, He celebrates his marriage to Mut in His name of Kamutef ("Bull of His Mother"). As Kamutef, the timelessness of succession is ultimately preserved, for it becomes truly reiterative and safe from mortal turmoils and the confusion of dynastic change.
Mut is Queen Mother and Queen Regnant above all, and Her name is "mother"; she is a woman entitled to wear the Double Crown. She may also wear the vulture headdress (as is appropriate to Her name), but is typically seen with a human head or that of a lion. As Amun rose to prominence, She replaced His original consort, Amaunet. She is among the lion goddesses with the title of the Eye of Ra; while She was the ruling matron, She also could be portrayed ithyphallically, able to wield a level of warlike authority typically reserved for male deities. While She is the mother of the king, She is not typically portrayed in a manner that suggests sexuality rather than rulership. She may also have been self-created, a parthenogenic deity responsible for creation.
Khonsu, the completion of the triad, is god of the moon, whose name means "traveller" or "wanderer"; his headdress is the lunar disc and crescent. While he was mentioned earlier, primarily as a fierce and bloodthirsty deity, his prominence as a significant deity is, again, a New Kingdom manifestation; He was noted as a manifestation of Amun as creator in the Khonsu Cosmogony. As He gained prominence He also became known for healing powers. As a lunar deity He governed the measurement of time; as a manifestation of creation He had influence over the development of pregnancy and gestation and an apparent role in birth. He wound up with some associations with Heru as another important son in a significant state triad; it is worth noting in passing that the Eye of Heru is a lunar symbol.
So.
We have here three figures associated in part with creation, all of whom have a creator aspect, all of whom have some role in mythic or practical (mammalian) reproduction. That reproductive cycle is linked with the king, and has no beginning or end (due to the presence of the Kamutef figure); the presence of the lunar deity also can serve as a reminder that the royal ka, like the moon, is eternal, even as the phases of the moon come and go like the lives of individual kings. The cycle is eternal, not contingent.
This creative triad travels from its regular home at Karnak in order to recelebrate its marriage and the bonds with the king; it travels forth as an emanation of the sort of numinous holiness that Amun brings. The royal ka is a vessel for that sanctity, and affirming the connection between the divine source and the king ensures that that can continue to spread from the spiritual world into the material.
When we welcome Amun and His family, we open to the hidden power that underlies all, to the secret strength of the wind. As They come, there is transformation and rebirth, for the lunar Eye is great enough to encompass the wholeness that includes even its wounding. Creative power spills forth, governed with ferocity and might, in all the ebbs and flows of being, in every flutter of the air.
Most unique of the unique, who made all that is,
who began the world back in the First Time;
Whose features are hidden, yet frequent his appearances,
and there is no knowing how he flowed forth;
Gloriously powerful, beloved, majestic,
mighty in his theophanies, magnificent;
Powerful Being through whose Being each Being came to be,
who began Becoming with none but himself.
- Papyrus Cairo 58032
References:
Foster, John L., trans. Hollis, Susan Tower, ed. Hymns, Prayers, and Songs: An Anthology of Ancient Egyptian Lyric Poetry. Atlanta, Georgia: Scholars Press, 1995.
Redford, Donald. B. The Ancient Gods Speak: A Guide to Egyptian Religion. Oxford: Oxford University Press, 2002.
Shaw, Ian and Nicholson, Paul. The Dictionary of Ancient Egypt. New York: Harry N. Abrams, Inc. Publishers, 2003.
Wilkinson, Richard H. The Complete Gods and Goddesses of Ancient Egypt. New York: Thames & Hudson, 2003.