Observe your thoughts, and beware of what you have in your heart and your spirit, knowing that the demons put ideas into you so as to corrupt your soul by making it think of that which is not right, in order to turn your spirit from the consideration of your sins and of God.
Remember always that, once we have decided consciously to strive after righteousness, we cannot escape catastrophes and sorrows, no matter where we are.
Think also of this: the person who is bound to earthly things may rejoice but may also be upset or disturbed or grieved over earthly things: his mind is exposed to continual changes. But the joy of your master (Matthew 25:21) is enduring, for God is unchangeable. Thus control your tongue at the same time as you discipline your body with fasting and strictness. Talkativeness is a great enemy of prayer. A spate of fluttering words stands in the way of the words of prayer. This is the reason that we shall render account for every careless word we utter (Matthew 12:36). One does not bring the dust of the road into a room that one wishes to keep clean; thus keep your heart free from gossip and chatter about the events of the day that is past.
Wherever we are and whatever our circumstances, the enemy always tries to prevent us from actively responding to the call. Pray for help. For help that you may never fail to respond. And beware lest, having received help and having done the right deed because of it, you should grow proud and acquire the habit of condemning others, in the secret chambers of your heart. Beware! For this would make all the fruits of your good works wither.
The enemy constantly endeavors to awaken in the abyss of the human heart a great turmoil about trifles. This is one of his tricks to blind our soul to the sun of truth, Christ our Lord, hidden in the heart's core of every one of our neighbors.
You ask for some way of completely eradicating irritability. The inclination to irritability is given us to use against sin, and we were never meant to use it against our fellow men. When we do, we act contrary to our true nature.
Always keep this in mind: you are not doing anything virtuous by your continence. Or can it be considered a virtuous act when a man who, out of his own carelessness, has been trapped deep down in a mine shaft, takes a pick and shovel and tries to work his way out? Is it not, on the contrary, quite natural for him to make use of the tools given him by a higher authority to make his way up out of the choking air and darkness? ...From this picture you can gain wisdom. The tools are the implements of salvation, the commands of the Gospel and the holy Sacraments of the Church, that were bestowed upon every Christian at holy baptism. Unused, they are of no profit to you. But used in the right manner they will open your way to freedom and light.
Let him judge of another’s sin who has not on his conscience that which condemns himself. Let him judge who does not himself do what he judges must be punished in another; lest while judging the other he passes sentence upon himself. Let him give judgment on another’s sin who is not led to deliver it by any hate, by dislike, or foolish levity.
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.
Behold, this is the true and the Christian humility. In this you will be able to achieve victory over every vice, by attributing to God rather than to yourself the fact that you have won.
A prayer offered while one has any cause to reproach a fellow man is an impure prayer. There is only one whom the praying person may and must reproach, and that is himself. Without self-reproach, your prayer is as worthless as it is while you are reproaching someone else in your heart. Perhaps you ask: How can one learn this? The answer is: One learns it through prayer.
True joy is the joy of consolation, the joy that wells up in the knowledge of one's own weakness and the Lord's mercy, and that does not need the bared teeth of laughter to express itself.
Let us then not be ashamed to confess our sins unto the Lord. Shame indeed there is when each makes known his sins, but that shame, as it were, ploughs his land, removes the ever-recurring brambles, prunes and thorns, and gives life to the fruits which he believed were dead. Follow him who, by diligently ploughing his field, sought for eternal fruit: 'Being reviled we bless, being persecuted we endure, being defamed we entreat, we are made as the offscouring of the world' (Luke 13:7). If you plough after this fashion you will sow spiritual seed. Plough that you may get rid of sin and gain fruit. He ploughed so as to destroy in himself the last tendency to persecution. What more could Christ give to lead us on to the pursuit of perfection, than to convert and then give us for a teacher one who was a persecutor?
The Holy Fathers recommend 'moderate' fasting; one ought not to allow the body to be weakened too much, for then the soul, too, is harmed. Nor ought one to undertake fasting too suddenly; everything demands practice, and each one should look to his own nature and occupation. To choose among different kinds of food is to be condemned; all food is God-given, but it is advisable to avoid such kinds as add to the body's weight and appetite; strong spices, meat, spirituous drinks and such foods as are solely for the palate's enjoyment. For the rest, one may eat what is cheap and most easily available, they say. But by 'moderate' they mean one meal a day, and that one light enough not to fill the stomach to satiety.