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?'
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.
My brother, the passions are afflictions; and so the Lord does not excommunicate us because of them, but He says: 'Call upon me in the time of affliction; and I will deliver thee, and thou shalt glorify me'. Therefore, when beset by any kind of passion, there is nothing more useful than to call upon the Name of God. All we can do, weak as we are, is to flee for refuge to the Name of Jesus. For the passions, being demons, retreat if this Name is invoked.
An elderly monk said, 'Always, when you are tempted to criticize, you should put a question mark on the whole situation and not judge. For we do not know what is really going on.'
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.
Concerning fasting, do not grieve, as I have said to you before: God does not demand of anyone labors beyond his strength. And indeed, what is fasting if not a punishment of the body in order to humble a healthy body and make it infirm for passions, according to the word of the Apostle: 'When I am weak, then am I strong' (II Corinthians 12:10).
In words of boastfulness and self-justification there always lie concealed contrariness and pride, from which God turns away. After sinning one ought immediately to 'flee.' But, you will say, where? To the calm haven of heartfelt repentance. Every night before you go to sleep, tell God, the Knower of Hearts, all the sins you have committed in deed, word, and thought, and believe that God receives your heartfelt repentance. At the same time try to render your heart contrite by the memory of sudden death.
A monk is he who wants to sleep and does not sleep, who wants to eat and does not eat, who wants to drink and does not drink. A monk is distinguished by ‘continual forcing of nature.’
Then we say: 'Forgive us our trespasses as we forgive those who trespass against us.' Brothers, praying thus, we should very much fear lest the Lord reply to these words of our prayer: 'The judgments you give are the judgments you will get, and the amount you measure out is the amount you will be given.' And you who ask this, see whether you did to no one what you did not want done to you. Therefore before we hear these words of the Lord, brethren, let us first examine our hearts as to whether we are with justice asking of the Lord what we have not denied to those asking us. We ask that our trespasses be forgiven us. God hears and He wants to forgive us, but only if we first pardon those who ask us to do likewise.
What is self-justification? - Self-justification is when a man denies his sin, as we see in the case of Adam, Eve, Cain and others who have sinned but, wishing to justify themselves, denied their sin.
To pray with self-constraint is in our power, whereas to pray with compunction depends upon God. We must pray with what prayer we can, and for our self-constraint God will give us compunction also in due time, when this is pleasing to Him.