Lehrs was a senior teacher at the first Waldorf School in Stuttgart. In 1935, he emigrated to the Netherlands where he participated in a Waldorf school and then later to Britain. In 1952, he returned to Germany and worked as a lecturer at the newly established course in anthroposophical curative education in Eckwälden, where he remained until his death in 1979.
Together with Wilhelm Rath he contributed significantly to the organisation of the youth conference in which Rudolf Steiner held the lecture cycle “The Younger Generation” and which led to the founding of an Esoteric Youth Circle. He describes this in his autobiography “Gelebte Erwartung”.
Man or Matter, London 1951; Klostermann, Frankfurt am Main 1953; 3rd edition 1987. ISBN 3-465-00285-7.
Der rosenkreuzerische Impuls im Leben und Werk von Joachim Jungius und Thomas Traherne. (The Rosicrucian entrepreneurial impulse in the life and work of Joachim Jungius and Thomas Traherne). Freies Geistesleben (Studien und Versuche 5), Stuttgart 1962.
Vom Geist der Sinne: Zur Diätetik des Wahrnehmens. (From the mind of the senses: toward the dietetics of perceiving). Klostermann, Frankfurt am Main 1973, 3rd edition 1994. ISBN 978-3-465-02651-8.
Spiritual Science, Electricity and Michael Faraday, London, 1975.
Rosicrucian Foundations of the Age of Natural Science, Spring Valley, NY, 1976.