What to read after Rilke's Book of Hours?

At the beginning of this century, a young German poet returned from a journey to Russia, where he had immersed himself in the spirituality he discovered there. He "received" a series of poems about which he did not speak for a long time - he considered them sacred, and different from anything else he ever had done and ever would do again. This poet saw the coming darkness of the century, and saw the struggle we would have in our relationship to the divine. The poet was Rainer Maria Rilke, and these love poems to God make up his Book of Hours.