The Philokalia

by Nicodemus of the Holy Mountain

34. If a man exercises only sensory discrimination between pain and pleasure in the body, thus transgressing the divine commandment, he eats from the tree of the knowledge of good and evil, that is to say, he succumbs; to the mindless impulses that pertain to the senses; for he possesses only the body's power of discrimination, which makes him embrace pleasure as something good and avoid pain as something evil. Bat if he exercises only that noetic discrimination which distinguishes between the eternal and the transitory, and so keeps the divine commandment, he eats from the tree of life, that is to say, from the wisdom that appertains to his intellect; for he exercises only the power of discrimination associated with the soul, which makes him cleave to the glory of what is eternal as something good, and avoid the corruption of what is transitory as something evil.