Rudolf Steiner wrote the text of the "Warmth Meditation" on two sheets of A4 paper in neat handwriting and without revisions or corrections, complete with two small, sketch-like drawings. He gave the meditation to the medical student Helene von Grunelius in early 1923 and "described it as the way for medical practitioners to behold the etheric Christ." It was intended for use by her and her circle of friends in their medical studies. The warmth meditation became their central esoteric medical meditation and has been maintained and practiced by countless individuals during the past eight decades, becoming for many the existential core of their therapeutic practice and perspective.
Peter Selg's insightful book describes the historical context of meditation and some of its spiritual implications. Included are reproductions of the original meditation as written down by Rudolf Steiner and Ita Wegman.