Your past and present torments and sufferings are poured down upon you to test your faith and 'steel' it; they also work to curb your lusts and passions. Humble yourself. God gives help to the humble. Judgment of others, insistence on their shortcomings, can only increase the bitterness of your sorrow. Choose the better part.
Do not approach the words of the mysteries contained in the divine Scriptures without prayer and beseeching God for help, but say: 'Lord, grant me to perceive the power in them!' Reckon prayer to be the key to the true understanding of the divine Scriptures.
It is not possible for any man to draw near to Christ without tribulation, and without afflictions his righteousness cannot be preserved unchanged. If he puts an end to the labors that make righteousness increase, he will put an end to that which guards it, and his righteousness will be like unguarded treasure. And he will be like a gladiator surrounded by enemy ranks and stripped of his weapons, like a ship bereft of its sails and tackle, and like a garden deprived of its source of water.
Keep both eyes open. This is the measure of humility: if a man is humble he never thinks that he has been treated worse than he deserves. He stands so low in his own estimation that no one, however hard they try, can think more poorly of him than he thinks of himself.
Set as a goal the kindling of the fire of the spirit, so that the spiritual fire will burn in your heart and, gathering up all your strength into one, will begin to build your inner man and finally burn up the tares of your sins and passions.
You have the book of discourses by St. Macarius of Egypt. Kindly read the 19th discourse, concerning a Christian's duty to force himself to do good. There it is written, 'One must force oneself to pray, even if one has no spiritual prayer.' And, 'In such a case, God, seeing that a man earnestly is striving, pushing himself against the will of his heart (that is, his thoughts), He grants him true prayer.' By true prayer, St. Macarius means the undistracted, collected, deep prayer that occurs when the mind stands unswervingly before God. As the mind begins to stand firmly before God, it discovers such sweetness, that it wishes to remain in true prayer forever, desiring nothing more.
If the main goal of the repentant sinner should be total, light-bearing and blessed communion with God, then the main hindrance to this is the existence of the passions still active and working in him - the virtues being as yet unsealed in him - and the unrighteousness of his powers. Therefore his main work upon conversion and repentance should be the uprooting of the passions and sealing the virtues - in a word, correcting himself.
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.
Life is hard for you? Why, is there anyone for whom it is not hard? And do those in the world really have no troubles? Be patient, and a comforter will come in time. The Lord said, `In your patience possess ye your souls' (Lk. 21:19). If you are unable to do something and your health does not permit it, humble yourself and beg meekly [to be excused] - and above all, be patient. And if you lose patience in some situation, reproach yourself and ask God for help.
How can one say that a man has attained purity? - When he sees all men as being good, and when none appears to him to be unclean and defiled - then he is indeed pure in heart.
As a general rule, decide whether a thing is permissible by the effect it produces within. Permit yourself what is constructive, but never what is destructive.
You are, I am sure, aware that for you penitence is now no longer limited to disclosing your sins to your confessor, but that you must now bear your sins in mind always, until your heart nearly breaks with their ugly load; and would break, were it not for your firm faith in the mercy of our Lord.