If you grew up in any mainstream Christian tradition, you probably didn't hear much about Sophia. Sophia — the Greek word for wisdom — appears throughout the Hebrew scriptures as a feminine personification of divine wisdom. In the Book of Proverbs, she speaks in the first person, claiming to have been present at the creation of the world, playing before God 'like a master craftsman.' She is intimate with God, active in creation, and available to those who seek her.
In Gnosticism
In Gnostic thought, Sophia becomes a much more dramatic figure. She is one of the divine emanations of the Pleroma, and her story is essentially the story of how the material world came to exist. In most Gnostic tellings, Sophia acts without her divine consort and 'falls' — produces something outside the proper divine order. This flawed production is the Demiurge, who then creates the material universe. The feminine divine doesn't just sit in the background. She causes the whole story.
Why this matters
Mainstream religion largely succeeded in removing the feminine divine from official theology. But the need it meets — for an accessible, intimate, relational face of the sacred — never went away. The Marian devotion of Catholic and Orthodox Christianity, the persistent appeal of goddess spirituality, the fascination with Sophia in modern esoteric circles: these are all, in different ways, the same need asserting itself.