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.
Our inner lives never get put into the proper order all of a sudden. What is always required and what lies ahead is intensified labor over oneself, over one's inner self, by the assimilation of good intention and by the enabling of grace through the Mysteries. This labor and effort is directed toward destroying the disorder that reigns inside, in its place it establishes order and harmony, after which follows inner peace and a continual joyful mood of the heart.
The origin of the Christian life is in arousal by grace. A person who has heeded this arousal is not then deprived of guidance by grace and communion with it at all times, as it persists through proper attention to it.
My children, desire to purify your hearts from envy and from anger with each other, lest death should overcome you, and you will be counted among the murderers. For whosoever hates his brother, kills a soul.
In preparing for battle, however, do not think that you will always be victorious. Often there will be only hardship that will bring nothing but affliction... Provide yourself with only one thing, strong courage: no matter what happens, stay with what you have begun... No matter how life goes, whatever successes and failures there are, you should give all of this over to God's will.
God in His mercy gave us the Holy Scriptures that we might read them, and reading them we might fulfill what is sent by God to man, revealing His Holy Will and teaching us how to live. Consider with what attention and willingness that we ought to read God's letter to us. If an earthly king...wrote to you a letter, would you not read it with great joy? Certainly, with great rejoicing and careful attention. The King of Heaven has sent a letter to you, an earthly and mortal man; yet you almost despise such a gift, so priceless a treasure. Whenever you read the Gospel, Christ Him self is speaking to you. And while you read, you are praying and talking with Him. God speaks to man, the King of Heaven talks with the corruptible creature, the Lord holds converse with the servant. What can be more pleasant... more instructive?
At this point the zealous man looks inward, and what do you think he finds there? Ceaseless wandering of thoughts, constant onslaughts from the passions, hardness and coldness of heart, obstinacy and disobedience, desire to do everything according to his own will. In a word, he finds everything within himself in a very bad state. And seeing this, his zeal is inflamed, and he now directs strenuous efforts to the development of his inner life, to controlling his thoughts and the dispositions of his heart. From directions on inner spiritual life he discovers the necessity of paying attention to oneself, of watching over the movements of the heart. In order not to admit to anything bad, it is necessary to preserve the remembrance of God. And so he sets to work to achieve this remembrance. But his thoughts can no more be arrested than the wind; his bad feelings and worthless impulses can no more be evaded than the stench of a corpse; his mind, like a wet and frozen bird, cannot rise to the remembrance of God. What is to be done? Be patient, they say, and go on working. Patience and labor are exercised, but all within remains the same. At last someone of experience is found who explains that all is inwardly in disorder because the forces within are divided: mind and heart each go their own way. Mind and heart must be united; then wandering of thoughts will cease, and you will gain a rudder to steer the ship of your soul, a lever by which to set in movement all your inner world. But how can one unite mind and heart? Acquire the habit of praying these words with the mind in the heart, 'Lord Jesus Christ, Son of God, have mercy upon me'. And this prayer, when you learn to perform it properly, or rather when it becomes grafted to the heart, will lead you to the end which you desire. It will unite your mind with your heart, it will cut off your wandering thoughts, and give you the power to govern the movements of your soul.
There is one method which, if practiced with full attention, will seldom allow anything passionate to slip unnoticed into the heart. This is to examine our thoughts and feelings, so as to discover which they tend: towards pleasing God or towards pleasing ourselves.
A truly intelligent man has only one care -- wholeheartedly to obey Almighty God and to please Him. The one and only thing he teaches his soul is how best to do things agreeable to God, thanking Him for His merciful Providence in whatever may happen in his life. For just as it would be unseemly not to thank physicians for curing our body, even when they give us bitter and unpleasant remedies, so too would it be to remain ungrateful to God for things that appear to us painful, failing to understand that everything happens through His Providence for our good. In this understanding and this faith in God lie salvation and peace of soul.
Since the enemy watches you constantly, waiting for an opportunity to sow evil in you, be doubly watchful over yourself, lest you fall in the nets spread for you. As soon as he shows you some fault in your neighbor, hasten to repel this thought, lest it take root in you and grow. Cast it out, so that no trace is left in you, and replace it by the thought of the good qualities you know your neighbor to possess, or of those people generally should have. If you still feel the impulse to pass judgment, add to this the truth that you are given no authority for this and that the moment you assume this authority you thereby make yourself worthy of judgment and condemnation, not before powerless men, but before God, the all-powerful Judge of all.
If you examine your life well, you will find many instances when God showed His unmistakable mercy to you. Trouble was brewing, but it passed you by for some reason. God delivered you. Acknowledge these and thank God, Who loves you.
The zealous are eager for ascetical struggles of self-forcing and self-opposition with the aim of self-correction, or of raising themselves to primordial purity, so that they might all the more speedily become worthy of communion with God. Obviously the more eager one is, the more diligently and longingly he does this, the sooner he achieves his goal.
Our life and our death is with our neighbor. If we gain our brother, we have gained God, but if we scandalize our brother, we have sinned against Christ.