I wonder if, in Malcom Guite's Galahad and the Grail, Book One, Stave IV, Balyn's sword in the stone is a type of the Theotokos as the New Eve. "It was my grandsire whom he maimed. Now I turn back the sword. The very sword that strikes and rends must be the sword that makes amends. I am the one the Spirit sends to heal both land and lord."