A man becomes spiritual insofar as he lives a spiritual life. He begins to see God in all things, to see His power and might in every manifestation. Always and everywhere he sees himself abiding in God and dependent on God for all things. But insofar as a man lives a bodily life, so much he does he do bodily things; He doesn't see God in anything, even in the the most wondrous manifestations of His Divine power. In all things he sees body, material, everywhere and always - "God is not before his eyes." (Ps. 35:2)
John of KronstadtThe accursed one does not allow the eye of the heart to see the Lord or His saints. He darkens our heart in every way. He scatters faith, oppressing, burning and darkening us inwardly. We must look upon all such actions as illusions and falsehood, and break through this imaginary wall to the Lord, or to His Holy Mother, or His saints. As soon as you break through this wall you will be immediately saved. 'Your faith has made you whole' (Mt. 9:22).
John of KronstadtHow will it be with us in the future life, when everything that has gratified us in this world: riches, honors, food and drink, dress, beautifully furnished dwellings, and all attractive objects-how will it be, I say, when all these things leave us-when they will all seem to us a dream, and when works of faith and virtue, of abstinence, purity, meekness, humility, mercy, patience, obedience, and others will be required of us?
John of Kronstadt