The heavenly is experienced through the Holy Spirit, and the earthly through the mind: whoever wants to experience God with his mind through learning is in vainglory, for God can only be experienced through the Holy Spirit.
I beseech you, put this to the test. When a man affronts you or brings dishonor on your head, or takes what is yours, or persecutes the Church, pray to the Lord, saying: 'O Lord, we are all Thy creatures. Have pity on Thy servants and turn their hearts to repentance,' and you will be aware of grace in your soul. To begin with, constrain your heart to love enemies, and the Lord, seeing your good will, will help you in all things, and experience itself will show you the way. But the man who thinks with malice of his enemies has not God's love within him, and does not know God.
An Athonite elder said, 'Blasphemous thoughts are like airplanes that annoy us, against our will, with their noise, and we are powerless to prevent them. The heavy anti-aircraft battery is psalmody, because it is both prayer to Christ and disdain for the devil.'
The Saints in Heaven through the Holy Spirit behold the glory of God and the beauty of the Lord's Countenance. But in this same Holy Spirit they see our lives too, and our deeds. They know our sorrows and hear our burning prayers. When they were living on earth they learned of the love of God from the Holy Spirit: and he who knows love on earth takes it with him into eternal life in the Kingdom of Heaven, where love grows and becomes perfect. And if love makes one unable to forget a brother here, how much more must the Saints remember and pray for us!
According to St. Gregory the Sinaite there are three degrees in eating: temperance, sufficiency, and satiety. Temperance is when someone wants to eat some more food but abstains, rising from the table still somewhat hungry. Sufficiency is when someone eats what is needed and sufficient for normal nourishment. Satiety is when someone eats more than enough and is more than satisfied. Now if you cannot keep the first two degrees and you proceed to the third, then, at least, do not become a glutton, remembering the words of the lord: 'Woe unto you that are full now, for you shall hunger' (Lk. 6:25). Remember also that rich man who ate in this present life sumptuously every day, but who was deprived of the desired bosom of Abraham in the next life, simply because of this sumptuous eating.
I shall indicate to you the most direct and simple method to acquire the habit of silence: ...reflect as often as you can on the pernicious results of indiscriminate babbling and on the salutary results of wise silence. When you come to taste the good fruit of silence, you will no longer need lessons about it.
I must tell you that annoying incidents are unavoidable in this life. Those who are experienced in the spiritual life say that such incidents can even bring profit to the soul. Through annoying incidents we come to recognize that we are impatient - and if we are impatient, that means we are proud. And this awareness should dispose us to self-reproach and repentance, and to asking mercy from the Lord in prayer. But without annoying incidents a man is inclined to conceit.
Tedium is the granddaughter of despondency, and the daughter of slothfulness. In order to drive it away, labor at your work, and do not be slothful in prayer. The tedium will pass, and zeal will come. And if to this you add patience and humility, then you will be rid of all misfortunes and evils.
The Saints were people just like ourselves. Many of them started with grievous sins but through repentance they attained the Kingdom of Heaven. And every one who comes to the Kingdom of Heaven does so through repentance which the Merciful Lord granted us by His sufferings. In the Kingdom of Heaven, the holy Saints look upon the glory of our Lord Jesus Christ; but through the Holy Spirit they see, too, the sufferings of men on earth. The Lord gave them such great grace that they embrace the whole world with their love. They see and know how we languish in affliction, how our hearts have withered within us, how despondency has fettered our souls, and they never cease to intercede for us to God.
Have great concern for these portals the eyes. Most robbers enter through these portals to overthrow the castle of the soul. Had the forefathers guarded their eyes, they would not have been exiled far from God and Paradise. 'The woman saw that the fruit of the tree was good...' (Gn 3:6).
You write that after Communion you felt well. Glory be to God, Who comforts our unworthiness. And as regards the fact that this soon passed, here also is seen His fatherly providence for us. For continual consolation enfeebles the soul and makes it slothful, or leads to even greater harm. That is why the Lord takes it away quickly and again makes us feel our weakness, our helplessness, and our sinfulness. We must humble ourselves more, reproach ourselves, offer repentance for our sins, and not desire consolations, but patiently endure what God allows. Dryness and cooling of fervor are also permitted on account of vainglory.
Our enemies (demons) fell because of their pride, and call us to follow them, and bring us feelings of praise. And if your soul accepts that praise, then grace will depart, until the soul becomes humble again. And so all your life you must learn the humility of Christ.
In patience is the assembly of all the virtues by which our souls are saved, as St. Ephraim says: having acquired patience, one touches on every virtue; for one rejoices in sorrows, and is well-tried in misfortunes, is joyful in danger, ready for obedience, filled with love, glories in vexation, is humbled in reproaches, unwavering in misfortunes; he who has acquired patience has acquired hope, and such a one is adorned with every good work.