The reason that fasting has an effect on the spirits of evil rests in its powerful effect on our own spirit. A body subdued by fasting brings the human spirit freedom, strength, sobriety, purity, and keen discernment.
Wherever we are and whatever our circumstances, the enemy always tries to prevent us from actively responding to the call. Pray for help. For help that you may never fail to respond. And beware lest, having received help and having done the right deed because of it, you should grow proud and acquire the habit of condemning others, in the secret chambers of your heart. Beware! For this would make all the fruits of your good works wither.
If a king wanted to take possession of his enemy's city, he would begin by cutting off the water and the food and so his enemies, dying of hunger, would submit to him. It is the same with the passions of the flesh; if a man goes about fasting and hungry the enemies of his soul grow weak.
Knowing the exact nature of everything, God permits each person to be tested according to his strength. As St. Paul puts it: 'God is to be trusted not to let you be tried beyond your strength, but with the trial He will provide a way out, so that you are able to bear it' (1 Cor. 10:13).
How harmful is the praise of man! Even though a person may have done something worthy of praise, when he enjoys the sound of praise he is already deprived of future glory, according to teachings of the holy fathers.
The most important thing in any good effort and the height of all activities is to persevere in prayer, by means of which we can always acquire through supplication the other virtues from God as well.
Unless humility and love, simplicity and goodness regulate our prayer, this prayer - or, rather, this pretence of prayer - cannot profit us at all. And this applies not only to prayer, but to every labor and hardship undertaken for the sake of virtue.
You are, I am sure, aware that for you penitence is now no longer limited to disclosing your sins to your confessor, but that you must now bear your sins in mind always, until your heart nearly breaks with their ugly load; and would break, were it not for your firm faith in the mercy of our Lord.
One of the Fathers said: just as it is impossible for a man to see his face in troubled water, so too the soul, unless it be cleansed of alien thoughts, cannot pray to God in contemplation.
Compunction comes when you consider how much you have grieved God Who is so good, so sweet, so merciful, so kind, and entirely full of love; Who was crucified and suffered everything for us. When you meditate on these things and other things the Lord has suffered, they bring compunction.
The soul of all practices in the Lord is vigilance. Without vigilance, all these practices are fruitless. He who is desirous of saving himself must so establish himself that he might remain continuously vigilant toward himself, not only in solitude, but also under conditions of distraction, into which he is sometimes unwillingly drawn by circumstances.
Faith is truly a gift, gained for us through Christ's advent. But this does not abolish our freedom or responsibility. God desires of us not only faith but action too.
Even a pious person is not immune to spiritual sickness if he does not have a wise guide -- either a living person or a spiritual writer. This sickness is called prelest, or spiritual delusion, imagining oneself to be near to God and to the realm of the divine and supernatural. Even zealous ascetics in monasteries are sometimes subject to this delusion, but of course, laymen who are zealous in external struggles (podvigi) undergo it much more frequently. Surpassing their acquaintances in struggles of prayer and fasting, they imagine that they are seers of divine visions, or at least of dreams inspired by grace. In every event of their lives, they see special intentional directions from God or their guardian angel. And then they start imagining that they are God's elect, and often try to foretell the future. The Holy Fathers armed themselves against nothing so fiercely as against this sickness -- prelest.
This is the mark of Christianity--however much a man toils, and however many righteousnesses he performs, to feel that he has done nothing, and in fasting to say, 'This is not fasting,' and in praying, 'This is not prayer,' and in perseverance at prayer, 'I have shown no perseverance; I am only just beginning to practice and to take pains;' and even if he is righteous before God, he should say, 'I am not righteous, not I; I do not take pains, but only make a beginning every day.'