The kingdom of God is within us when God reigns in us, when the soul in its depths confesses God as its master, and is obedient to Him in all its powers. Then God acts within it as master ‘both to will and to do of his good pleasure’ (Phil. ii. 13). This reign begins as soon as we resolve to serve God in our Lord Jesus Christ, by the grace of the Holy Spirit. Then the Christian hands over to God his consciousness and freedom, which comprises the essential substance of our human life, and God accepts the sacrifice; and in this way the alliance of man with God and God with man is achieved, and the covenant with God, which was severed by the fall and continues to be severed by our willful sins, is re-established. This inner alliance is sealed, confirmed, and given the strength to maintain itself by the power of grace in the divine sacrament of baptism, and for those who have fallen after baptism, in the sacrament of repentance: and afterwards it is constantly strengthened by holy communion. All Christians live thus; and consequently they all bear the kingdom of God within themselves, that is to say they obey God as King and are ruled by God as King.
You ask, 'Must one do something?' Of course one must! And do whatever comes along-in your circle of friends and in your surroundings-and believe that this is and will be your real work. More will not be demanded of you. It is a great misconception to think, whether for the sake of heaven or, as the modernists put it, to 'make one's mark on humanity,' that one must undertake great, reverberating tasks. Not at all. It is necessary only to do everything according to the commandments of God. Just what exactly? Nothing in particular - only those things which present themselves to everyone in the circumstances of life, those things which are required by the everyday happenings we all encounter. Let's take an example: a beggar comes up to you; it is God Who has brought him. God has brought you the beggar, of course, desiring you to act toward this beggar in a manner pleasing to Him, and He watches to see what you will actually do. It will please Him if you help. Will you? If you do what is pleasing to God, you will be taking a step toward the ultimate goal, the inheritance of heaven. Generalize this occurrence, and you will find that in every situation and at every encounter one must do what God wants him to do. And we know truly what He wants from the commandments He has given us. If someone seeks help, then help him. If someone has offended you, forgive him. If you yourself have offended someone, then hasten to ask forgiveness and to make peace. If someone has praised you, do not be proud. If someone has scolded you, do not get angry. If the time has come to pray, then pray. To work, then work, - etc. etc.
My brother, the passions are afflictions; and so the Lord does not excommunicate us because of them, but He says: 'Call upon me in the time of affliction; and I will deliver thee, and thou shalt glorify me'. Therefore, when beset by any kind of passion, there is nothing more useful than to call upon the Name of God. All we can do, weak as we are, is to flee for refuge to the Name of Jesus. For the passions, being demons, retreat if this Name is invoked.
From this minute of his new life, the repentant sinner commences his podvig, struggle, and labor, and begins to bear the burden, the yoke. This is so essential that all the saints accept the only true path to virtue to be pain and hard work. On the contrary, lightness and ease are a sign of a false path, for the kingdom of God suffereth violence, and the violent take it by force (Matt. 11:12). Anyone who is not struggling, not in podvig, is in prelest.
Concerning fasting, do not grieve, as I have said to you before: God does not demand of anyone labors beyond his strength. And indeed, what is fasting if not a punishment of the body in order to humble a healthy body and make it infirm for passions, according to the word of the Apostle: 'When I am weak, then am I strong' (II Corinthians 12:10).
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.
Most men not only bear Satan's burden willingly in their hearts, but they become so accustomed to it that they often do not feel it, and even imperceptibly increase it. Sometimes, however, the evil enemy increases his burden tenfold, and then they become terribly despondent and fainthearted, they murmur and blaspheme God's name. The usual means that men... take to drive away their anguish are... entertainments... But such means afterwards increase still more the anguish and weariness of their hearts. If, happily, they turn to God, then the burden is removed from their heart, and they clearly see that previously the heaviest burden was lying on their heart, though frequently they did not feel it.
All men are made in God's image; but to be in His likeness is granted only to those who through great love have brought their own freedom in subjection to God... Free will is the power of a deiform soul to direct itself by deliberate choice towards whatever it decides.
Imagine how resplendently adorned, what a pure and perfect palace of the Almighty must have been the most holy soul and the most pure body of the Mother of God, in whose womb God the Word-Godhead, soul and body-came to dwell! Imagine how eternal, infinite, unchangeable is her holiness! Imagine of what reverence she is worthy, how we should glorify her!
Oh, what great happiness and bliss, what exaltation it is to address oneself to the Eternal Father. Always, without fail, value this joy which has been accorded to you by God's infinite grace and do not forget it during your prayers; God, the angels and God's holy men listen to you.
The day will come when you are toiling at self-observation and self-constraint, and the adversary will come up and mumble in your ear, 'This will all happen eventually. You’ve been working hard, now take it easy a little bit!' This is such a tempting suggestion that it does not immediately occur to you that you should counter it, or that it is so bad that however little you give in to it, it will cause such inner disturbance. Indulging yourself is just like a tiny hole in a dam. Once a hole has formed, the dam cannot hold; the water will inevitably destroy it. Indulgence does the same thing inside of us; everything will be dispersed, so it will be necessary to start all over again to restore ourselves. Fear this as your most evil enemy, although he speaks with the sweetest words.
May simplicity go before you everywhere; especially be simple in your faith, hope, and love, for God is an Essence of Simplicity, a Unity that is worshipped everlastingly, and our soul is simple. The simplicity of our soul is hindered by our flesh, when we please it.
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.
Monasticism itself is a perpetual labor of conquering passions and uprooting them in order that, being in a pure and immaculate state, one may preserve oneself before the face of God. This, then, is your task! Give your attention to it, and direct all your powers towards it.
Your enemy, the evil one, the father of lies, does not slumber; and endeavors, by every means open to him, to harden your heart --- to make it false and crafty, to drive out from it faith and hope in God - together with love for Him and love and sympathy for your neighbor - and to occupy you with worldly, temporal interests. Watch yourself, watch the thoughts of your heart, and do not bind yourself in the chains of worldly desires and pleasures. Let your happiness be in the one God and the human soul.
The incessant invocation of God's name is a medicine which mortifies not just the passions, but even their influence. Just as the physician puts medications or dressings on a wound that it might be healed, without the patient even knowing the manner of their operation, so also the name of God, when we invoke it, mortifies all passions, though we do not know how that happens.