" we assert that when a rock is in the ground it is, after a fashion, in its center, even though it is not in its deepest center, for it is within the sphere of its center, activity, and movement; yet we do not assert that it has reached its deepest center, which is the middle of the earth. Thus the rock always possesses the power, strength, and inclination to go deeper and reach the ultimate and deepest center; and this it would do if the hindrance were removed. When once it arrives and no longer has any power or inclination toward further movement, we declare that it is in its deepest center. 12. The soul's center is God. When it has reached God with all the capacity of its being and the strength of its operation and inclination, it will have attained its final and deepest center in God, it will know, love, and enjoy God with all its might. When it has not reached this point (as happens in this mortal life, in which the soul cannot reach God with all its strength, even though in its center - which is God through grace and his self-communication to it), it still has movement and strength for advancing further and is not satisfied. Although it is in its center, it is not yet in its deepest center, for it can go deeper in God. "

― John of the Cross , The Collected Works of St. John of the Cross