O nobly-born, when thy body and mind were separating, thou must have experienced a glimpse of the Pure Truth, subtle, sparkling, bright, dazzling, glorious, and radiantly awesome, in appearance like a mirage moving across a landscape in springtime in one continuous stream of vibrations. Be not daunted thereby, nor terrified, nor awed. That is the radiance of thine own true nature. Recognize it. From the midst of that radiance, the natural sound of Reality, reverberating like a thousand thunders simultaneously sounding, will come. That is the natural sound of thine own real self. Be not daunted thereby, nor terrified, nor awed. O nobly-born, five-colored radiances . . . vibrating and dazzling like colored threads, flashing, radiant, and transparent, glorious and awe-inspiring, will . . . strike against thy heart, so bright that the eye cannot bear to look upon them. . . . Be not afraid of that brilliant radiance of five colors, nor terrified; but know that Wisdom to be thine own. Within those radiances, the natural sound of the Truth will reverberate like a thousand thunders. The sound will come with a rolling reverberation. Fear not. Flee not. Be not terrified. Know them to be thine own inner light.
— The Tibetan Book of the Dead , edited by Dr. W. Y. Evans-Wentz