Though the Egyptian Solar calendar reflected the three agricultural seasons of the Nile Valley, the cycle of the four celestial periods was recognized and viewed as the ascent and descent of Solar powers in the visible world. This is the Solar passage through the constellations along the ecliptical belt of the sky throughout the tropical year, beginning at the spring equinox, when night and day are equal in length, and symbolically, when body and soul are in balance between the visible and invisible worlds. In ancient times this period coincided with the return of the constellation Orion in the night sky, a harbinger of the powers of Asar becoming renewed.
The Egyptians were particularly watchful of the solstices, the summer solstice coinciding with the Nile’s initial inundation and the winter solstice marking the time of planting after the waters had receded. Each was observed with elaborate temple festivities that honored the Neteru whose powers had become renewed and visible in the sky and on Earth. The autumnal equinox marked the lengthening of night and the gradual diminishment of Orion in the sky; hence, it was associated with the waning powers of the Solar gods and the incipient rule of dark forces.
The ingress (entry) of the Sun into the constellations is a metaphor of the soul’s entry into the dimension of conscious creation. Ra, the divine creator, is the Neter who brings forth the five senses (Heka, Sia, Hu, Maa, Sedjem) and in the process endows all in the visible realms with the creative powers he embodies. The annual rhythm of the twelve Solar ingresses through the Zodiacal mansions represents the construction of the body of light, which is assumed by the temple initiate prior to meeting the gods in cosmic realms. The theme of the body correspondence with cosmic principles is still inherent in the astrological “rulerships” of the signs-their governing of regions of the body, physical functions, and metaphysical faculties.
— Rosemary Clark: The Sacred Magic of Ancient Egypt