Verses and Meditations is an extensive collection of verses given by Rudolf Steiner to individuals and groups between 1906 and 1925. It is a personal favorite of mine, and I have used various of the verses for meditation and reflection at different points in my life over the past 20 or so years. I still go back to it several times a year and always find something “new” and valuable to me personally.
I should also note that the Introduction by George Adams is an excellent discussion of anthroposophic inner work and meditation. It is thorough, concise and engaging – an unbeatable combination, really. The carefully selected verses plus this essay is also an unbeatable combination – I can attest to the longevity of its usefulness.