Anyone nowadays acknowledges that smacking someone with your hand is something very real, that it actually happens. But it not so easily believed that it is just as real when I send someone a bad thought. We must be aware that the hostile thought that I send to my fellow human being, the thought of antipathy or hatred, is to his soul the same as a slap in the face would be. A negative feeling, a feeling of hatred and indifference with which I confront another person is in reality the same as a physical injury.
Source (German): Rudolf Steiner – GA 264 – Zur Geschichte und aus den Inhalten der ersten Abteilung der Esoterischen Schule 1904 – 1914 (page 373-374)
Translated by Nesta Carsten-Krüger
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