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.
The weather shifts from cloudy to clear and then back to rain; thus it is with human nature. One must always expect clouds to hide the sun sometimes. Even the saints have had their dark hours, days and weeks. They say then that 'God has left them' in order that they may know truly how utterly wretched they are of themselves, without His support. These times of darkness, when all seems meaningless, ridiculous and vain, when one is beset by doubt and temptations, are inevitable. But even these times can be harvested for good. The dark days can best be conquered by following the example of St. Mary of Egypt. For forty-eight years she dwelt in the desert beyond Jordan, and when temptations befell her and memories of her former sinful life in Alexandria beckoned her to leave her voluntary sojourn in the desert, she lay on the ground, cried to God for help and did not get up until her heart was humbled. The first years were hard; she sometimes had to lie this way for many days; but after seventeen years came the time of rest. On such days stay quiet. Do not be persuaded to go out into social life or entertainment. Do not pity yourself, seek comfort in nothing but your cry to the Lord: 'Haste thee, O God, to deliver me! Makes haste to help me, O Lord (Psalm 70:1)! I am so fast in prison that I cannot get forth (Psalm 88:8),' and other such appeals. You cannot expect real help from any other source. For the sake of chance relief do not throw away all your winnings. Pull the covers over your head; now your patience and steadfastness are being tried. If you endure the trial, thank God who gave you the strength. If you do not, rise up promptly, pray for mercy and think: I got what I deserved! For the fall itself was your punishment. You had relied too much on yourself, and now you see what it led to. You have had an experience; do not forget to give thanks.
One should not ponder divine matters on a full stomach, say the ascetics. For the well-fed, even the most superficial secrets of the Trinity lie hidden.
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.
God smiles on the compassionate heart. Every time a beggar knocks at your door, try to perceive Christ Himself under the humble disguise. Would you, under any circumstances, let Christ knock in vain? The moral qualities of the individual beggar have nothing to do with it; that is Christ's concern, not yours. Who are you to judge your brother? Christ is using the beggar’s hand and mouth to test your compassion of Himself. Will you fail Him?
You must set about rooting out the very desire to have things pleasant, to get on well, to be contented. You must learn to like sadness, poverty, pain, hardship. You must learn to follow privately the Lord's bidding: not to speak empty words, not to adorn yourself, always to obey authority, not to look at a woman with desire, not to be angry and much else. For all these biddings are given us not in order for us to act as if they did not exist, but for us to follow: otherwise the Lord of mercy would not have burdened us with them. If any man will come after me, let him deny himself, He said (Matthew 16:24), thereby leaving it to each person's own will ... and to each person's endeavor: let him deny himself.
If you wish to be delivered from shameful passions, do not behave with anyone familiarly, especially with those toward whom your heart is inclined by a lustful passion; through this you will be delivered also from vainglory. For in vainglory is involved the pleasing of men, in the pleasing of men is involved familiarity of behavior, and familiarity of behavior is the mother of all passions.
Leave off all evasions, bend your neck to humility and obedience, and you will receive mercy. If you practice with humility and obedience what you hear from the fathers, God will grant you His blessed help not only in the work you are doing, but will make all your works successful, for He protects the path of those who fear Him and watches their progress.
The holy Fathers' counsel is to begin with small things, for, says Ephraim the Syrian, how can you put out a great fire before you have learned to quench a small one? If you wish to set yourself free from a great suffering, crush the small desires, say the holy Fathers. Do not suppose that the one can be separated from the others: they all hang together like a long chain or a net.
No, the God of love and peace and complete sacrifice does not care to live in the midst of bustling and ado to please oneself, even if this is carried on perhaps under some kind of pretence. There is one way to make a test: if your peace of mind is troubled, if you become dejected or perhaps a little angry if for some reason you have to give up performing the good deed you had planned, then you know that the spring was muddy.
Do not think that even here any one of us constantly enjoys consolation. No: here, as everywhere, flesh and mind are at war; here as everywhere, there is falling into pride and purification through humbling: here, as everywhere, we long for consolations but must learn to carry a weighty cross. This cross tests our love. Can we, do we love God even under the weight of the most bitter adversities?
According to the teaching of the Fathers, any impression which, touching the heart, fills it with a great irritation, must come from the region of passions. Therefore impulses which spring from the heart should not be followed at once, but only after careful examination and fervent prayer. God preserve us from a blind heart! It is well known that passions do blind the heart and screen the shining sun of the mind that we should all strive to gaze at.