Do not be surprised that when you draw near to virtue, grievous and intense tribulations come to you on all sides: for virtue is not considered virtue, if it does not involve hard work.
Brothers, as long as you have breath in your bodies, strive for your salvation. Before the hour comes in which we shall weep for ourselves, let us practice virtue eagerly. For I tell you that if you knew what good things are in heaven, what promise is laid up for the saints and how those who have fallen away from God are punished and also what torments are laid up for those who have been negligent – especially those who have known the truth and have not led a way of life worthy of it so as to inherit that blessedness which is reserved for the saints and to flee the punishments of these torments – then you would endure every pain in order to be made perfect in the virtue which is according to Christ.
A Christian has great difficulty in attaining three things: grief (over sins), tears, and the continual memory of death. Yet these contain all of the other virtues.
We ought not to grieve or become irritated at anything because, by frequent vexation and irritability, we form the morally and physically very injurious habit of irritability, whilst by bearing opposition with equanimity we form the good and useful habit of enduring everything calmly and patiently.
Just as one cannot buy education or artistic skills for any price without working at it, so one cannot attain the habit of exercising the virtues without zeal and diligence.
I think it best that a man should have a little bit of all the virtues. Therefore, get up early every day and acquire the beginning of every virtue and every commandment of God. Use great patience, with fear and long-suffering, in the love of God, with all the fervor of your soul and body. Exercise great humility, bear with interior distress; be vigilant and pray often with reverence and groaning, with purity of speech and control of your eyes. When you are despised do not get angry; be at peace, and do not render evil for evil. Do not pay attention to the faults of others, and do not try to compare yourself with others, knowing you are less than every created thing. Renounce everything material and that which is of the flesh. Live by the cross, in warfare, in poverty of spirit, in voluntary spiritual asceticism, in fasting, penitence and tears, in discernment, in purity of soul, taking hold of that which is good. Do your work in peace. Persevere in keeping vigil, in hunger and thirst, in cold and nakedness, and in sufferings. Shut yourself in a tomb as though you were already dead, so that at all times you will think death is near.
Holiness is not simply righteousness, for which the righteous are rewarded with blessedness in the Kingdom of God; rather, it is such a height of righteousness that people are so filled with the grace of God that it flows from them even upon those who associate with them. Great is their blessedness, which proceeds from their direct contemplation of the glory of God. Being filled also with love for men, which proceeds from love of God, they are responsive to men's needs, and at their entreaties they act as mediators and intercessors for them before God.
The blacksmith, who pounds a piece of iron, has previously thought about what he wants to make- a sickle, a knife, an axe - and works accordingly. And so let the man of God ponder in advance which virtue he wishes to acquire, in order not to toil aimlessly.
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.
If we fervently desire holiness, the Holy Spirit at the outset gives the soul a full and conscious taste of God’s sweetness, so that the intellect will know exactly of what the final reward of the spiritual life consists.