Book excerpt: In this selection of thirty of Rudolf Steiner's most important lectures on the Festivals, he identifies and illumines the true meaning behind Christmas, Easter, Ascension and Pentecost, and Michaelmas, emphasizing both their inner-spiritual and outer-cosmic aspects. He shows that the Festivals are not merely the commemoration of mighty historical events or truths within the Christian tradition, but are in themselves - each year - spiritual events, manifesting in seasonal and natural rhythms, which carry a significance that grows and deepens with the developing of human evolution.