Excerpt from the Surangama Sutra, i.e. Sutra of the Indestructible - by Buddha

Nevertheless, since beings have allowed their attention to be drawn to sights and sounds and have allowed themselves to be carried along in their streams of thought, as it has been since time without beginning, they have not yet awakened and do not yet understand the purity, the wondrousness, and the permanence of their own essential nature. Instead of attending to what is everlasting, they attend to what comes into being and perishes, and as a result, in life after life, they are mired in impurity and are bound to the cycle of death and rebirth. But if they turn away from what comes into being and perishes and hold fast to what is true and everlasting, then the light of the everlasting will appear, and as a result the faculties, their objects, and the sense-consciousnesses will fade away and disappear.

By entirely disengaging yourself from two impurities -- defiled mental processes and defiled emotional attachment to those processes -- your Dharma-eye will become clear and bright. How then could you fail to go on to realize a supreme understanding and awakening?