Rudolf Steiner: "Let us imagine that we face someone who meets us with disparagement and insult. If we have dwelt long enough upon the teachings of reincarnation and karma, we will be able to ask who it is who has uttered injurious or insulting words that have penetrated our ears and overwhelmed us with their scorn, and may even have raised their hand to strike us. And we will be able to reply: We ourselves! The hand is only seemingly that of the other person, for I am myself the person who, through my past karma, solicited the blow that the other has given me."
Source: June 5, 1911. The Mission the the New Spirit Revelation, p. 140