Vision of the Satan in Immense Light

St Isaac the Syrian. "The Ascetical Homilies".

A person called Malpa, who came from Edessa, was the author of the heresy of Euchites but he was a great ascetic and went through the harshest ascetical practices. It is said that in time of being a disciple of Julian the Blessed, also called Sava, he visited with him for a short time Mt Sinai and Egypt and there heard mysterious homilies of St Anthony about the purity and salvation of the soul. St Anthony was explaining that the mind made pure can contemplate the mysteries of the Holy Spirit and the soul by God’s grace can become passionless if only keeps the commandments and returns to its primitive healthy nature of Eden.

The beginning of Prelest is Slothfulness with Regard to the Prayer and the Divine Services

St Isaac of Syria, The Ascetical Homilies, Homily 2.

The beginning of mind derangement (when it becomes visible in the soul) is to be seen, first of all, in slothfulness with regard to the Divine services and prayer. For except the soul first fall away from these, she cannot be led in the way of error; but as soon as she is deprived of God’s help, she easily falls into the hands of her adversaries. And again, whenever the soul becomes heedless of the labours of virtue, she is inevitably drawn to what is opposed to them. A transition, from whichever side it occurs, is the beginning of what belongs to the opposite party. Practice the work of virtue in your soul and do not concern yourself with futile matters. Always lay bare your weakness before God, and you will never be put to the test by aliens when you are found alone, distant from your Helper.

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Many Misfortunes May Be Permitted by God Due to Sloth

Venerable Isaac the Syrian. "Ascetical Homilies".

217. Therefore, the Lord leaves the reasons for humility and contrition of the heart in intensified prayer to His Saints, so that those who love Him will come closer to Him through humility. And often frightens them with the passions of their nature and the creeps of shameful and unclean thoughts, and often with reproaches, insults and slaps from people, sometimes with bodily illnesses and ailments, at other times, with poverty and lack of necessary things, then with excruciating strong fear, abandonment, obvious attacks of the devil, and various terrible incidents. And all this in order for them to have reasons for humility and not to fall into the sleep of sloth.

http://oprelesti.ru/index.php/what-is-spiritual-delusion/815-many-misfortunes-may-be-permitted-by-god-due-to-sloth

You can not Solicit Gifts of God Ahead of Time

St. Isaac the Syrian. "Ascetic Words." Word 55.

One of the saints wrote: "If one does not consider himself a sinner, his prayer is not accepted by the Lord." If you say that some fathers wrote, what is purity of heart, what is health, what is dispassion, what is contemplation, they wrote not in order to make us strive for that ahead of time; for it is written that the kingdom of God cometh not with observation (Lk.17: 20) of expectation. And those who had such intention, they obtained pride and fall. And we will arrange the region of the heart by repentance and life pleasing to God; what is given by the Lord comes by itself, if the place in the heart is pure and undefiled. What we are looking for with observation, I mean high Divine gifts, is not approved by the Church of God; and those who accepted that, they obtained pride and fall. And this is not a sign that a person loves God, but mental illness. And how can we strive for high Divine gifts, when Paul glories in tribulations and considers the fellowship of the sufferings of Christ to be a high God's gift.

http://oprelesti.ru/index.php/kinds-of-spiritual-delusion/147-expectation-of-gifts-from-god/658-you-can-not-solicit-gifts-of-god-ahead-of-time