Someone asked a Tibetan lama if he was afraid that by breathing in others' suffering during tonglen meditation practice, he would catch it. To this he replied that nothing would make him happier than to take on their pain so they could be free of it. When someone can say this, a profound shift has taken place. His greatest happiness comes from realizing the equality of himself and others. Whatever pain he experiences in the process is not a deterrent.
— Pema Chodron, No Time to Lose