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.
And as with regard to raiment and gold, when we expose them in a market-place, we attract many ill-meaning persons; but if we put them by at home and hide them, we shall deposit them all in security: even so with respect to our good deeds; if we are continually keeping them in memory, we provoke the Lord, we arm the enemy, we invite him to steal them away; but if no one know of them, besides Him who alone ought to know, they will lie in safety. Be not therefore for ever parading them, lest some one should take them away. As was the case with the Pharisee, for bearing them about upon his lips; whence also the devil caught them away. And yet it was with thanksgiving he made mention of them, and referred the whole to God. But not even did this suffice Him. For it is not thanksgiving to revile others, to be vainglorious before many, to exalt one's self against them that have offended. Rather, if thou art giving thanks to God, be content with Him only, and publish it not unto men, neither condemn thy neighbor; for this is not thanksgiving.
What is it that commends our own life? Is it miracles, or is it a life scrupulously and uprightly lived? It is rather from the latter that miracles arise, and to that they tend. For he that lives a worthy life, draws this grace upon himself; and whosoever receives such graces receives them that he may help others to amend their lives. For even Christ wrought miracles that He might the more be accepted as worthy of belief, and so might the more attract men to Himself, and by this means bring sanctity into their lives.
When we live according to the moral principles of our faith, those around us may respond in three possible ways. First, they may be so impressed by the example of our goodness, and so envious of the joy which it brings, that they want to join us and become like us. That is the response which we most earnestly desire. Second, they may be indifferent to us, because they are so bound up with their own selfish cares and concerns; although their eyes may perceive our way of life, their hearts are blind, so we are unable to stir them. Third, they may react against us, feeling threatened by our example and even angry with us; thus they will cling even more firmly to their material possessions and selfish ambitions, and slander us at every opportunity. Naturally, we dread this third type of reaction, because we want to live in peace with our neighbors, regardless of their personal beliefs and values. But if no one reacts to us in this way, we must wonder whether we are truly fulfilling the commandments of Christ.
When someone is beginning the spiritual life, he should not study a lot, but instead watch himself and guard his thoughts. A strong person is the one who chews well, not the one who eats a lot.
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.
Fasting, while of value in itself, is not something to boast of in front of God, for it is simply a tool for training those who desire self-restraint. The ascetic should not feel proud because he fasts; no artist ever boasts that his accomplishment is simply due to his tools; but he waits for the work itself to give proof of his skill.
Even if we have thousands of acts of great virtue to our credit, our confidence in being heard must be based on God's mercy and His love for men. Even if we stand at the very summit of virtue, it is by mercy that we shall be saved.
Wherefore, do not remember your good deeds, in order that God may remember them. Do thou first confess thy sins, it is written, that thou mayest be justified (Isaiah 43:26).
