The awareness of mortals falls short. As long as they're attached to appearances, they're unaware that their minds are empty. And by mistakenly clinging to the appearance of things they lose the Way.
. . . the fools of this world prefer to look for sages far away. They don't believe that the wisdom of their own mind is the sage . . . the sutras say, "Mind is the teaching." But people of no understanding don't believe in their own mind or that by understanding this teaching they can become a sage. They prefer to look for distant knowledge and long for things in space, buddha-images, light, incense, and colors. They fall prey to falsehood and lose their minds to insanity.
Leaving behind the false, return to the true: make no discriminations between self and others. In contemplation, one's mind should be stable and unmoving, like a wall.