“Guard your heart!” These words were spoken in the past by experienced ascetics. Father John of Kronstadt says the same thing in our days: “The heart is refined, spiritual and heavenly by nature. Guard it. Do not overburden it; do not make it earthly; be temperate to the utmost in food and drink, and in bodily pleasures in general. The heart is the temple of God. If any man defile the temple of God, him shall God destroy (I Corinthians 3:17).” Spiritual experience in ancient times and spiritual experience in our time is identical, under the condition that the confession of faith is identical. The heavenly knowledge to which the ascetics of old attained does not differ from the heavenly knowledge to which the ascetics of today attain. For, as Christ is the same today and tomorrow, so it is with human nature. The main thing is: the human heart is the same; its thirst and its hunger are the same; and nothing is able to satisfy it but the glory, power and riches of God.
Saint Nikolai Velimirovich
~Prologue of Ohrid reflection