Sin, to one who loves God, is nothing other than an arrow from the enemy in battle. The true Christian is a warrior fighting his way through the regiments of the unseen enemy to his heavenly homeland.
A true Christian is made by faith and love toward Christ. Our sins do not in the least hinder our Christianity, according to the word of the Savior Himself. He deigned to say: not the righteous have I come to call, but sinners to salvation; there is more joy in heaven over one who repents then over ninety righteous ones. Likewise concerning the sinful woman who touched His feet, He deigned to say to the Pharisee Simon: to one who has love, a great debt is forgiven, but from one who has no love, even a small debt will be demanded. From these judgments a Christian should bring himself to hope and joy, and not in the least accept an inflicted despair. Here one needs the shield of faith.
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.
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.
What do we do when attacked by some criminal? We strike out at him and shout for help. Our cries are answered by the police, who then rescue us from danger. We must do the same in inner warfare with the passions. Filled with anger against them, call for assistance: Help me, O Lord! Jesus Christ, Son of God, save me! O God, make speed to save me! O Lord make haste to help me! Having thus called on the Lord, do not allow your attention to wander from Him, do not let it turn to what is happening within you, but go on standing before the Lord and imploring His help. This will make the enemy run away as though pursued by flames.
To more conveniently become accustomed to remembering God, the fervent Christian has a special means, namely, to repeat ceaselessly a brief prayer of two or three words. Mostly this is 'Lord, have mercy.' or 'Lord Jesus Christ, Son of God, have mercy on me, a sinner.' If you have not yet heard of this, then hear it now, and if you have not done it, then begin from this hour to do it.
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.
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.
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.
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.
Whoever is experienced in the spiritual interpretation of Scripture knows that the simplest passage is of a significance equal to that of the most abstruse passage, and that both are directed to the salvation of man.
Have great concern for these portals the eyes. Most robbers enter through these portals to overthrow the castle of the soul. Had the forefathers guarded their eyes, they would not have been exiled far from God and Paradise. 'The woman saw that the fruit of the tree was good...' (Gn 3:6).
If you love to enjoy true and complete delight from the Scriptures, seek to read them not merely with simple understanding, but with deeds and practical realities. Moreover, seek to read them not merely for the mere love of learning but also for the sake of ascetic endeavors & discipline, as St. Mark wrote: 'Read the words of Holy Scripture with an eye to practical applications and not merely to be puffed up by any fine thought that you may receive from it.' Another Father said: 'This is why the lover of knowledge must also be a lover of discipline. For knowledge alone does not give light to a lamp.'
Do not by any means allow yourself to open both ears to the slanderers and to draw your conclusions and decisions on the basis of what they alone have to say, and thereby judging the case in absentia without the presence of the person slandered to defend himself. Oftentimes many unjust and irrational decisions have followed from such slanderous accusations.
Such are the souls of the saints: they love their enemies more than themselves, and in this age and in the age to come they put their neighbor first in all things, even though because of his ill-will he may be their enemy.