Practice self-observation. And if you want to benefit yourself and your fellow men, look at your own faults and not those of others. The Lord tells us: 'Judge not, that ye be not judged,' condemn not that ye be not condemned. And the Apostle Paul says: 'Who art thou that judgest another man's servant?'
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.'
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.
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.
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.
For forgiveness of sins is most efficaciously prayed for with almsgiving and fasting, and supplications that are winged by such aids mount swiftly to God’s ears; since it is written, 'the merciful man doeth good to his own soul' (Prov. xi. 17), and nothing is so much a man’s own as that which he spends on his neighbor. For that part of his material possessions with which he ministers to the needy, is transformed into eternal riches, and such wealth is begotten of this bountifulness as can never be diminished or in any way destroyed, for 'blessed are the merciful, for God shall have mercy on them' (Matt. v.7), and He himself shall be their chief Reward, who is the Model of His own command.
Repentance is real when afterwards you keep trying strenuously to live now as you ought; but without this it is not very effectual, if you repent just to say your sins & to keep on living as before.
A mind that dwells on everyday matters of life and vain things disperses the soul. One should turn inwardly, looking at the soul’s uncultivated vineyard, weeding it of all evil thorns and planting virtues there instead. But be wary, for this type of work is not easy at all. It requires perseverance and much patience. One will be confronted with a multitude of difficulties. Various writings of the Fathers are very helpful, and in our days are available by the dozens. In them one can find anything his heart desires, and anything it needs. The Fathers will lead you on the right spiritual path, if only you read them with humility and prayer.
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.
Confess your sins not to the priest, but to the Lord Himself, only without hiding anything, from your whole heart. The priest is the mediator between you and God, and so the benefit of Confession depends on your open-heartedness.