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 best medicine for pride, man’s greatest sickness of soul, is humility. Words cannot describe or explain it, but the Fathers say that he who strives hard to live according to the precepts of our Lord, and is fully aware of his own sins, acquires it steadily. Therefore be very careful never to think yourself good, or the least bit better than others.
When you go to your spiritual father for confession, do not bring yourself as an accuser of other people, saying, 'he said this,' and 'so-and-so said that'. . . but speak about your own doings, so that you may obtain forgiveness.
The proof of authenticity of the spiritual condition of a father confessor is, that while he is very strict with himself, he is very lenient with others and does not use the canons of the Church like cannons against them.
St. Paul says: 'The person engaged in spiritual warfare exercises self control in all things' (I Cor. 9:25). Aware of all that is said in divine Scripture, let us lead our life with self-control, especially in regard to food.
Therefore with your whole soul you should acknowledge yourself as worthy of enduring more than you already endure; remember the words which Christ the Savior spoke concerning a good deed done to one's neighbor, words which should apply equally to every offensive word or deed against one's neighbor. Whatever you have done to your neighbor, He says, you have done to Me.