Fire makes iron impossible to touch, and likewise frequent prayer renders the intellect more forceful in its warfare with the enemy. That is why the demons strive with all their strength to make us slothful in attentiveness to prayer, for they know that prayer is the intellect's invincible weapon against them.
Acts of charity, almsgiving and all the external good works do not suppress the arrogance of the heart; but noetic meditation, the labor of repentance, contrition and humility -- these humble the proud mind.
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.
Do all in your power not to fall, for the strong athlete should not fall. But if you do fall, get up again at once and continue the contest. Even if you fall a thousand times because of the withdrawal of God's grace, rise up again each time, and keep on doing this until the day of your death. For it is written, 'If a righteous man falls down seven times' - that is, repeatedly throughout his life - 'seven times shall he rise again' [Prov. 24:16].
If we fervently desire holiness, the Holy Spirit at the outset gives the soul a full and conscious taste of God’s sweetness, so that the intellect will know exactly of what the final reward of the spiritual life consists.
When the door of steam baths is continually left open, the heat inside rapidly escapes through it; likewise the soul in its desire to say many things, dissipates the remembrance of God through the door of speech, even though everything it says may be good. Ideas of value always shun verbosity, being foreign to confusion and fantasy. Timely silence, then, is precious, for it is nothing less than the mother of the wisest thoughts.
You have no peace from thoughts, which impel you to trouble others, and in turn to be troubled by others. But know, my brother, that if we offend by word or deed, we are thereby ourselves offended a hundredfold. Be longsuffering in all things and refrain from letting your own will enter into anything. Carefully examine your thoughts lest they infect your heart with deadly poison (ill temper) and make you take a gnat for a camel, a pebble for a cliff, and lest you become like a man who has a beam in his own eye but beholds the mote in the eye of another.
Remember, O my soul, the terrible and frightful wonder: that your Creator for your sake became Man, and deigned to suffer for the sake of your salvation. His angels tremble, the Cherubim are terrified, the Seraphim are in fear, and all the heavenly powers ceaselessly give praise; and you, unfortunate soul, remain in laziness. At least from this time forth arise and do not put off, my beloved soul, holy repentance, contrition of heart and penance for your sins.
Leave off all evasions, bend your neck to humility and obedience, and you will receive mercy. If you practice with humility and obedience what you hear from the fathers, God will grant you His blessed help not only in the work you are doing, but will make all your works successful, for He protects the path of those who fear Him and watches their progress.
For the complete fulfillment of its [the intellect's] purpose we should give it nothing but the prayer 'Lord Jesus'...Those who meditate unceasingly upon this glorious and holy name in the depths of their heart can sometimes see the light of their own intellect. For when the mind is closely concentrated upon this name, then we grow fully conscious that the name is burning up all filth which covers the surface of the soul; for it is written: 'our God is a consuming fire' (Deut. 4:24). Then the Lord awakens in the soul a great love for His glory...This is the pearl of great price which a man can acquire by selling all that he has, and so experience the inexpressible joy of making it his own.
When can someone understand human suffering? When he also suffers. When he goes through the same, he learns and understands the other person's suffering. Otherwise, he is callous and is not grieved, unless he happens to have a good nature. But all natural attributes merit neither honor nor dishonor; achievements and falls depend on our own free will.