Do not say that it is impossible to receive the Spirit of God.
Do not say that it is possible to be made whole without Him.
Do not say that one can possess Him without knowing it.
Do not say that God does not manifest Himself to man.
Do not say that men cannot perceive the divine light, or that it is impossible in this age!
Never is it found to be impossible, my friends.
On the contrary, it is entirely possible when one desires it.
-- St Symeon the New Theologian, Hymn 27.