The mind is the root of every defilement. It is here that anger is born; and from anger, every kind of hurt and injury to others: fighting, beating, and the rest. The mind is the soil in which all this grows: all malevolence, envy, desire, stupidity, arrogance, and so forth. That is why the Buddha told us to get a grip on our minds.
— Dudjom Rinpoche, Counsels From My Heart