People usually believe an “enemy” is someone outside, a certain animal, a particular organization, etc. Buddhism asserts our real enemy is not outside; the most fearsome enemy is inside – it is our self-attachment.

The ancients say: “Fortune and misfortune do not come through the door; only we ourselves invite them.” The happiness and suffering we experience are entirely of our own choosing. If not for one’s innate attributes, nothing can harm us – not the raging fire in hell, the hunger and thirst in the hungry ghost realm, or the evil spirits and wild beasts in this world. Our foremost enemy is self-attachment. It is this attachment that gives rise to greed, anger, delusion, and arrogance.

- Quote from The Four Seals of Dhama, "All Phenomena Lack Self-Existence"