This state of presence is extraordinarily important to know and taste in oneself. For sacred tradition is emphatic in its insistence that real Wisdom can be given and received only in a state of presence, with all three centers of our being engaged and awake. Anything less is known in the tradition as "sleep" and results in an immediate loss of receptivity to higher meaning. To return to that favorite Wisdom metaphor, it is like the disciple Peter suddenly sinking beneath the surface of the waters.
The saints speak of something they call the inextinguishable light. It is a light not of the eye but of the heart that never ceases to walk in purity and clearness. It swiftly leaves the darkness behind, and constantly strives towards the day's height. Its constant quality is to be continually purified. This is the light of eternity that can never go out, and that shines through the veil of time and matter. The saints never say that this light is given to them, but that it is given only to those who have purified their hearts in love for the Lord, on the narrow way which they have freely chosen.