If some Christians cannot comprehend our Orthodox faith, its Sacraments, it proves that the minds and hearts of such persons are too impure and passionate to bear its purity and brightness, just as sick eyes cannot bear the light of the sun. This heavenly treasure can only be comprehended by the hearts of those who free their minds and feelings from worldly attachments.
Our soul is simple as thought, and rapid as thought or lightning. In an instant it can be wounded by sin and become attached to corruptible things; in an instant it can fall away from the love of God and its neighbor through a single unrighteous thought, through a single passionate desire, through a single malevolent thought, and, therefore, we must constantly watch our heart, lest it should incline to words or thoughts of evil, and must ever strive to preserve it in God's simplicity and purity, and in the love of God and its neighbor.
'If our prayer is not in harmony with our deeds, we labor in vain,' Abba Moses often told the young monks. 'How are we to accomplish such harmony?' they asked him one day. 'When we make that which we seek fitting to our prayer,' explained the saint. 'Only then can the soul be reconciled with its Creator and its prayer be acceptable, when it sets aside all of its own evil intentions.'
You see how bright the sun and the stars are. 'Then shall the righteous shine forth as the sun' from the inner immaterial light of God. Whenever the angels appear upon earth, they are almost always surrounded by light. Aspire to that enlightenment. Throw aside the works of darkness. We can raise our nature to communion with the Divine Nature; and God is the Light uncreated, surpassing every light that has been created.
It is well known that obedience is the chief among the initiatory virtues, for first it displaces presumption and then it engenders humility within us. Thus it becomes, for those who willingly embrace it, a door leading to the love of God. It was because he rejected humility that Adam fell into the lowest depths of Hades. It was because He loved humility that the Lord, in accordance with the divine purpose, was obedient to his His Father even to the cross and death, although He was in no way inferior to the Father; and so through His obedience He has freed mankind from the crime of disobedience and leads back to the blessedness of eternal life all who live in obedience. Thus humility should be the first concern of those who are fighting the presumption of the devil, for as we advance it will be a sure guide to all the paths of virtue.
Your enemy, the evil one, the father of lies, does not slumber; and endeavors, by every means open to him, to harden your heart --- to make it false and crafty, to drive out from it faith and hope in God - together with love for Him and love and sympathy for your neighbor - and to occupy you with worldly, temporal interests. Watch yourself, watch the thoughts of your heart, and do not bind yourself in the chains of worldly desires and pleasures. Let your happiness be in the one God and the human soul.
Reverence with all the powers of your soul all the sacraments, and say to yourself in respect to every sacrament before the celebration or the communion of it: `This is God's mystery. I myself am only the unworthy witness or partaker of it.' Otherwise our proud intellect even wishes to search out God's mystery, and, if unable to penetrate it, rejects it as not coming under the small measure of our intellect.
As earth thrown over it extinguishes a fire burning in a stove, so worldly cares and every kind of attachment to something, however small and insignificant, destroys the warmth of the heart which was there at first.
When praying, endeavor by every means to feel in your heart the truth and the power of the words of the prayer; feed yourself upon them as upon an imperishable food; water your heart with them as with a dew; and warm yourself by them as by means of a beneficial fire.
A man standing on the seashore sees the immense expanse of water, but his eye can embrace only a small part and cannot reach its limit. In the same way, a man who, through contemplation, is given to see the limitless ocean of Divine glory and to see God Himself with the eyes of his mind, sees God and the infinite vastness of His glory, though not the whole as it really is, but only as much as is possible for him.
Have you realized that the world and worldly cares do not hinder in fulfilling God's commandments, when there is zeal and attention? That silence and retirement from the world are useless, if laziness and negligence prevail?