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.
The man who is conscious of his sins is greater than he who profits the whole world by the sight of his countenance. The man who sighs over his soul for but one hour is greater than he who raises the dead by his prayer while dwelling amid many men.
Do not be surprised that when you draw near to virtue, grievous and intense tribulations come to you on all sides: for virtue is not considered virtue, if it does not involve hard work.
Be despised and rejected in your own eyes, and you will see the glory of God within yourself. For where humility blossoms, there God’s glory bursts forth.
The Law (as it is written in the Scriptures) was given to us by Angels and, both before and after the days of the Law, Angels guided our illustrious forefathers to God, either by declaring to them what they should do and leading them from error and an evil life to the straight path of truth, or by making known to them the Divine Law, or in the manner of interpreters, by showing to them holy Hierarchies, or secret visions of super-mundane Mysteries, or certain divine prophecies. Now if anyone should say that God has shown Himself without intermediary to certain holy men, let him know beyond doubt, from the most Holy Scriptures, that no man has ever seen, nor shall see, the hidden Being of God; but God has shown himself, according to revelations which are fitting to God, to His faithful servants in holy visions adapted to the nature of the seer.
If you have no works, do not speak on virtues. Afflictions suffered for the Lord's sake are more precious to Him than every vow and sacrifice; and the odor of their sweet surpasses every fragrance.
As it is not possible to cross over the great ocean without a ship, so no one can attain to love without fear. The fetid sea, which lies between us and the noetic paradise, we may cross by the boat of repentance, whose oarsmen are those of fear. But if fear's oarsmen do not pilot the ship of repentance whereby we cross over the sea of this world to God, we shall be drowned in the fetid abyss. Repentance is the ship and fear is the pilot; love is the divine haven.
The kingdom of God is always present for him who desires and wills it. When a man's disposition and way of life are like that of an angel, most assuredly this is the kingdom of God. For God indeed is said to rule as King when nothing worldly meddles in the governing of our souls and when in every respect we live not of this world. This manner of life we have within us, that is to say, we have it within us when we desire and will it. We do not need to wait a long time, or until our departure from this life; instead, faith and a God-pleasing life which accompanies faith are very near us.