Time, like space, has four cardinal points, which are the two equinoxes and two solstices of the year. The winter solstice takes place on 21 December and is presided over by the Archangel Gabriel. And on 25 December, the feast of Christmas celebrates a birth, in other words a concretization, a descent into matter. The Archangel Gabriel directs forces whose specific task is the condensing of matter.
This is why, on the sephirotic tree, Gabriel is the Archangel of Yesod, the region of the Moon. Unlike the Sun, which dilates, disperses and distributes, the Moon compresses, contracts and condenses. If it were not checked by other influences, it would petrify all life in plants, animals and humans. Initiates, who are instructed in this science, try to use the period of the winter solstice to make their ideas and plans concrete, for this is the time when a birth takes place on earth.
The other cardinal feasts correspond to other processes: Easter, to resurrection; St. John’s day, to the kindling of fire; Michaelmas, to a stripping away. The feast of Christmas is linked to an incarnation, and this is why the birth of Christ, in the person of Jesus, has traditionally taken place in winter.
Izvor Book 36, Angels and other Mysteries of the Tree of Life