Love all the Brighid representations in this art work by Danielle Barlow , most of the Brighd symbols I knew but not how the serpent was linked to her.
I did a bit of research and found that according to Celtic mythology an awakening hibernating serpent will emerged from it's lair at Imbolc, and by it's movements it was calculated how many more days of winter there would be, if it returned to it's lair then spring wold be a month or more in coming. Although Brigid is a triple goddess she is mainly thought of as a spring goddess, so as she is to usher in spring this would be imported to know. Serpents also represent new life and fertility, much like spring, as well as transformation, creativity and inspiration,
Paths of Earth energy, ley lines, were also called serpent paths and at Imbolc they are stirred from their slumber as the earth warms.