In Vita Merlini, Merlin goes quite mad for a while, speaking of Britain in the past and remarking on nature and religion. He makes grand prophecies of what will happen in the future - he is, after all, a prophet. All of this happens while he resides in the woods, in a house with 70 windows and doors.
After he regains his sanity, his sister, Ganieda, and his friends Maeldin and Taliesin decide to turn their backs on the outside and world and live with him in his house in the woods.
The chieftains departed. The three remained, and with them a fourth--Ganieda, the prophet's sister, who had finally taken to their way of life also. She had been leading a retired life since the death of the king. She who till now had been the queen of a large nation under the appointed law, now found nothing pleasanter than living in the woods with her brother. She, too, was from time to time exalted in spirit to sing often of the future of the kingdom. So, one day when she stood in her brother's hall and gazed at the house and at its windows glittering in the sun, she uttered these dark sayings out of a dark heart:
"I see the city of Oxford filled with helmeted men, and holy men and holy bishops bound on the decision of the Council.
. . .
She did not end with this, and her friends listened in amazement. So also did her brother, who after a while went up to her and congratulated her in kindly words, saying, "Sister, is it you the spirit has willed to foretell the future? He has curbed my tongue and closed my book. Then this task is given to you. Be glad of it, and under my authority declare everything faithfully."
Throughout the whole story, Merlin seems to have attributed many things in the world that have helped him to God. Yet his remark at the end - about "the spirit" - seems a bit cryptic.
Who does Merlin attribute his - and his sister's - gift of prophecy to? Is it God, or something else (perhaps the same being who caused his madness, leading him to the woods)?