Do not befoul your intellect by clinging to thoughts filled with anger and sensual desire. Otherwise you will lose your capacity for pure prayer and fall victim to the demon of listlessness.
One must by every means strive to preserve peace of soul and not be disturbed by offenses from others; for this one must in every way strive to restrain anger and by means of attentiveness to keep the mind and heart from improper feelings. And therefore we must bear offenses from others with equanimity and accustom ourselves to such a disposition of spirit that these offenses seem to concern not us, but others. Such a practice can give quietness to the human heart and make it as dwelling for God Himself.
Conscience in men is nothing else but the voice of the omnipresent God moving in the hearts of men, as He Who alone Is and has created everything, the Lord knows all as Himself - all the thoughts, desires, intentions, words, and works of men, present, past, and future. However far in front I may let my thoughts, my imagination, run He is there before me and I ever inevitably finish my course in Him, ever having Him as the witness of my ways. 'His eyes are open upon all the ways of the sons of men' (Jer 32:19). 'Whither shall I go from Thy Spirit, or whither shall I flee from Thy presence?' (Ps 139:7).
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.
It is necessary most of all for one who is fasting to curb anger, to accustom himself to meekness and condescension, to have a contrite heart, to repulse impure thoughts and desires, to examine his conscience, to put his mind to the test and to verify what good has been done by us in this or any other week, and which deficiency we have corrected in ourselves in the present week. This is true fasting.
The first step toward freedom from anger is to keep the lips silent when the heart is stirred; the next, to keep thoughts silent when the soul is upset; the last, to be totally calm when unclean winds are blowing.
It is not possible for a man to control his anger when abused, or to overcome trials with patience when afflicted, if he is not willing to take the last and lowest place among other men.
When anyone is disturbed or saddened under the pretext of a good and soul-profiting matter, and is angered against his neighbor, it is evident that this is not according to God: for everything that is of God is peaceful and useful and leads a man to humility and to judging himself.
Of the Only Case in Which Anger is Good... But we have a use for anger most properly planted within us, and for this use alone it is profitable and healthful for us to entertain it, namely, when we burn with wrathful indignation against the lustful motions of our own hearts, and are enraged to find that those things which we should be ashamed to do or to speak of before men have found admittance into the secret places of our minds. We may then well dread and fear exceedingly the presence of the Angels and the Omnipresence of God Himself, and His all-seeing Eye from which no secrets of our hearts can lie hid.
Empty your mind of these two things: the belief that you are deserving of great things, or the thought that any man is beneath you. If you do this anger will never be permitted to rise up within you.