Sri Aurobindo translates Prashna Upanishad, First Question, Verses 9-13: “The year also is that Eternal Father and of the year there are two paths, the northern solstice and the southern. Now they who worship God with the well dug and the oblation offered, deeming these to be righteousness, conquer their heavens of the Moon: these return again to the world of birth. Therefore do the souls of sages who have not yet put from them the desire of offspring, take the way of the southern solstice which is the road of the Fathers. And this also is Matter, the Female. But by the way of the northern solstice go the souls that have sought the Spirit through holiness and knowledge and faith and askesis: for they conquer their heavens of the Sun. There is the resting place of the breaths, there immortality casteth out fear, there is the highest heaven of spirits: thence no soul returneth: therefore is the wall and barrier. Whereof this is the Scripture: Five-portioned, some say, is the Father and hath twelve figures and he floweth in the upper hemisphere beyond the heavens: but others speak of him as the Wisdom who standeth in a chariot of six spokes and seven wheels. The month also is that Eternal Father, whereof the dark fortnight is Matter the Female and the bright fortnight is Life the Male. Therefore do one manner of sages offer sacrifice in the bright fortnight and another in the dark. Day and night also are the Eternal Father, whereof the day is Life and the night is Matter. Therefore do they offend against their own life who take joy with woman by day: by night who take joy, enact holiness.”
The motions of the earth revolving around the sun create two major periods in the cycle, the northern and the southern solstice periods. During one period the sun (prana) is more intense and has a more powerful influence on the earth. Similarly, the month is divided into two halves, this time related to the influence of the moon (earth). And then there is the division between day and night, which once again sets forth another energetic cycle moving within the larger lunar and solar cycles. The divisions spoken of include the 12 months, and, as based in India, either the 5 or 6 seasons of the year.
There is a time and a season for all things, and these are formed by the interactions of Life (Prana) and Matter and the cyclical markings of Time to manifest the universal creation based on the Knowledge of the One Eternal that is systematically rolling out the creation through these divisions of Time.
There is also a psychological component that looks at the energetic action of these different cycles and applies it to the focus and energy of the seeker. There are those who seek the perpetuation of the creation and the race, who follow the energy of the southern solstice, and then there are those who seek the silent, ineffable Oneness of the Eternal, who follow the path of the northern solstice.
Sri Aurobindo, The Upanishads, Prashna Upanishad, pp.297-315