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.
Stillness mortifies the outward senses and resurrects the inward movements, whereas agitation does the opposite, that is, it resurrects the outward senses and deadens the inward movements.
Love of God proceeds from conversing with him; this conversation of prayer comes about through stillness, and stillness comes with the stripping away of the self.
We ought not to grieve or become irritated at anything because, by frequent vexation and irritability, we form the morally and physically very injurious habit of irritability, whilst by bearing opposition with equanimity we form the good and useful habit of enduring everything calmly and patiently.
