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.
Though remission of sins is given equally to all, the communion of the Holy Spirit is bestowed in proportion to each man's faith. If you have labored little, you receive little; but if you have wrought much, the reward is great. You are running for yourself, see to your own interest.
According to the degree to which the intellect is stripped of the passions, the Holy Spirit initiates the intellect into the mysteries of the age to be.
If however any one thinks that he is not being burned when sinning, to him the Scripture saith, Shall a man wrap up fire in his bosom, and not burn his clothes? For sin burns the sinews of the soul, and breaks the spiritual bones of the mind, and darkens the light of the heart.
But let thine apparel be plain, not for adornment, but for necessary conversing: not to minister to thy vanity, but to keep thee warm in winter, and to hide the unseemliness of the body: lest under the pretence of hiding the unseemliness, thou fall under another kind of unseemliness by thy extravagant dress.
In order, then, that Christ may win us all unto obedience, He promises us surpassing honors, and deigns us the highest love, saving, `My mother and My brethren are those who hear the word of God and do it.' For who among men is so obdurate and ungentle, as to refuse to honor, and accord the most complete love to his mother and brethren? For the all-powerful law of nature, even without our will, obliges us to this. When, therefore, bowing our neck to the Savior's commands, we become His followers, and so are in the relation of a mother and brethren to Him, how does He regard us before God's judgment seat? Is it not with gentleness and love? What doubt can there be of this?: And what is comparable to this honor and goodness? What is there worthy of being matched with a gift thus splendid and desirable?
We make mention [in the Divine Liturgy] also of the Seraphim, whom Isaiah in the Holy Spirit saw standing around the throne of God, and with two of their wings veiling their face, and with two their feet, while with two they did fly, crying 'Holy, Holy, Holy, is the Lord of Hosts' (Isaiah 6:2-3). For the reason of our reciting this confession of God, delivered down to us from the Seraphim, is this, that so we may be partakers with the hosts of the world above in their hymn of praise.
The view we take of our Savior's dispensation is the view of the holy fathers who preceded us. By reading their works we equip our own mind to follow them and to introduce no innovation into Orthodoxy.
We then commemorate also those who have fallen asleep before us, first, patriarchs, prophets, apostles, martyrs, that God, by their prayers and intercessions, may receive our petitions.
'And forgive us our debts as we also forgive our debtors.' For we have many sins. For we offend both in word and in thought, and very many things we do worthy of condemnation; and 'if we say that we have no sin' (I Jn. 1:8), we lie, as John says...The offenses committed against us are slight and trivial, and easily settled; but those which we have committed against God are great, and need such mercy as His only is. Take heed, therefore, lest for the slight and trivial sins against you, you shut out for yourself forgiveness from God for your very grievous sins.
Amongst the higher powers all things are done in due order, and with them there are limitations of honor or ministry, and boundaries are set for the glory of each by God who apportions all things as He sees fit. Yet there is a single yoke laid upon all, and they serve at the bidding of the Lord, not regarding their servitude as unworthy, but counting the reality of it as a source of honor and glory.