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.
Before the writing of the Holy Scriptures, that is, of the sacred texts of the Gospels, the Acts and the Epistles of the Apostles, and before they were spread to the churches of the world, the church was based on Sacred Tradition....The holy texts are in relation to Sacred Tradition what the part is to the whole.
Let us have recourse to humility on all occasions; for the humble lie prone on the ground, and how can a man fall if he lies on the ground? But a man who stands on a height can easily fall.
Leave off all evasions, bend your neck to humility and obedience, and you will receive mercy. If you practice with humility and obedience what you hear from the fathers, God will grant you His blessed help not only in the work you are doing, but will make all your works successful, for He protects the path of those who fear Him and watches their progress.
Give thanks to God for all things, because thanksgiving is intercession before God for our weakness. Judge yourself always and in everything as a sinner and as one seduced - and so God will not judge you; be humble in everything and you will receive grace.
The desire for possessions is dangerous and terrible, knowing no satiety; it drives the soul which it controls to the heights of evil. Therefore, let us drive it away vigorously from the beginning. For once it has become master it cannot be overcome.
When you intend to do something and see that your thought is perturbed, and if after invoking God's Name it remains perturbed even by a hair's breadth, know from this that the action you mean to commit is from the evil one and refrain from commiting it. For nothing done with perturbation is pleasing to God.
You have no peace from thoughts, which impel you to trouble others, and in turn to be troubled by others. But know, my brother, that if we offend by word or deed, we are thereby ourselves offended a hundredfold. Be longsuffering in all things and refrain from letting your own will enter into anything. Carefully examine your thoughts lest they infect your heart with deadly poison (ill temper) and make you take a gnat for a camel, a pebble for a cliff, and lest you become like a man who has a beam in his own eye but beholds the mote in the eye of another.
Fasting needn't be limited to abstinence from food alone, because true fasting is departure from evil deeds. Forgive your neighbor any insult, abstain from causing your neighbor offence, abstain from irritation, from senseless sorrows, from fear, wrath, and so on. ‘True fasting is alienation from evil, temperance of the tongue, setting aside of wrath, casting out of lust, idle talk, lies, and oath-breaking’…This is a true and pleasing fast for the Lord. Departing from these vices and from a corrupt state is what comprises a true fast.
Concerning fasting, do not grieve, as I have said to you before: God does not demand of anyone labors beyond his strength. And indeed, what is fasting if not a punishment of the body in order to humble a healthy body and make it infirm for passions, according to the word of the Apostle: 'When I am weak, then am I strong' (II Corinthians 12:10).
To act 'according to one’s strength' means to use a little less than necessary both of food, and drink, and sleep... As for food, restrain yourself when you wish to eat a little more, and in this way you will always make use of it moderately.
The flow of history confirms the reality of the Gospel: the Church is filled to overflowing with sinners. Does their presence in the Church reduce, violate, or destroy her sanctity? Not in the least! For her Head—the Lord Christ, and her Soul—the Holy Spirit, and her divine teaching, her mysteries, and her virtues, are indissolubly and immutably holy. The Church tolerates sinners, shelters them, and instructs them, that they may be awakened and roused to repentance and spiritual recovery and transfiguration; but they do not hinder the Church from being holy. Only unrepentant sinners, persistent in evil and godless malice, are cut off from the Church either by the visible action of the theanthropic authority of the Church or by the invisible action of divine judgment, so that thus also the holiness of the Church may be preserved.
Silence of lips is better and more wonderful than any edifying conversation. Strive to acquire humility and submissiveness. Never insist that anything should be according to your will, for this gives birth to anger. Do not judge or humiliate anyone, for this gives birth to anger. Do not judge or humiliate anyone, for this exhausts the heart and blinds the mind, and thereon leads to negligence and makes the heart unfeeling.
The more one reads and studies the Bible, the more he finds reasons to study it as often and as frequently as he can. According to St. John Chrysostom, it is like an aromatic root, which produces more and more aroma the more it is rubbed.