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.
The Holy Fathers teach us how to become familiar with the Gospel, how to read it and how to understand it, what helps and what opposes its understanding. Therefore, at first you must devote more time to reading the Holy Fathers...
In the Church we are freed from worldly enchantment, and from the intoxication of worldly passions and desires; we become enlightened, sanctified, cleansed in our souls; we draw near to God, we are united with God ('Who, by Thy glorious Childbirth, hath united God the Word with men') How worthily reverenced and loved should the temple of God be! How God’s Saints loved it!
In the grim struggle with the invisible enemies of our salvation, the supreme weapon is the prayer of Jesus. `All the nations' - the vociferous and wily demons are called nations - `surround me,' says David, `and in the name of the Lord I repulsed them. They encircled and surrounded me like bees, and they burnt like fire among thorns; and in the name of the Lord I repulsed them' (Ps. 117:10-12). With the name of Jesus flog the foes, because there is no stronger weapon in heaven or earth.
Our works in this life are the sowing, and the future life is the harvest of what we have sown. Whatever one sows here, that is what he shall reap there. If one hastens to cultivate the field of his heart, to fertilize it and to sow in it the seeds of immortal grain, he can confidently expect to see a corresponding harvest unto eternal rest and delight. He that sows with tears of repentance shall reap with rejoicing and 'shall be filled,' says the Prophet (Psalms 16:16 and 125:6), for sweet rest follows upon the labors of piety. But rest and refreshment are denied to him who has not labored in the work of piety-he that is idle should not eat, it is said (cf. II Thessalonians 3:10).
Keep a strict watch against any appearance of pride: it appears imperceptibly, particularly in time of vexation and irritability against others for quite unimportant causes.
The right practice of abstinence is needful not only to the mortification of the flesh but also to the purification of the mind. For the mind then only keeps holy and spiritual fast when it rejects the food of error and the poison of falsehood.
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.
Having guarded ourselves against distractions and worries, let us turn our attention to our body on which mental vigilance is completely dependent. Human bodies differ widely from one another in strength and health. Some by their strength are like copper and iron; others are frail like grass. For this reason everyone should rule his body with great prudence, after exploring his physical powers. For a strong and healthy body, special fasts and vigils are suitable; they make it lighter, and give the mind a special wakefulness. A weak body should be strengthened by food and sleep according to one's physical needs, but on no account to satiety. Satiety is extremely harmful even for a weak body; it weakens it, and makes it susceptible to disease. Wise temperance of the stomach is a door to all the virtues. Restrain the stomach, and you will enter Paradise. But if you please and pamper your stomach, you will hurl yourself over the precipice of bodily impurity, into the fire of wrath and fury, you will coarsen and darken your mind, and in this way you will ruin your powers of attention and self-control, your sobriety and vigilance…
Do not dare to raise your weak hand to stop the elemental tide of apostasy. Avoid it, protect yourself from it, and that is enough for you. Get to know the spirit of the times, study it so you can avoid its influence whenever possible.
There is nothing more efficacious against the wiles of the devil, dearly beloved, than the kindness of forgiveness, and the bountifulness in charity, by means of which sin is either avoided or overcome.
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.
The way to attain compunction is an attentive life. ‘The beginning of repentance comes from the fear of God and attention,’ as the holy martyr Boniface says.
The enemy of our salvation especially strives to draw our heart and mind away from God when we are about to serve Him, and endeavors to adulterously attach our heart to something irrelevant. Be always, every moment, with God, especially when you pray to Him. If you are inconstant, you will fall away from life, and will cast yourself into sorrow and straitness.
The images of worldly vanity, upon which we have looked with entire pleasure and hearty sympathy, effeminate, weaken, and disturb the soul; they deprive us of purity of heart and of boldness before God.