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.
A mind that dwells on everyday matters of life and vain things disperses the soul. One should turn inwardly, looking at the soul’s uncultivated vineyard, weeding it of all evil thorns and planting virtues there instead. But be wary, for this type of work is not easy at all. It requires perseverance and much patience. One will be confronted with a multitude of difficulties. Various writings of the Fathers are very helpful, and in our days are available by the dozens. In them one can find anything his heart desires, and anything it needs. The Fathers will lead you on the right spiritual path, if only you read them with humility and prayer.
Do not neglect the practice of the virtues; if you do, your spiritual knowledge will decrease, and when famine occurs you will go down into Egypt (Genesis 41:57, 46:6).
Even if a person’s sin is not only obvious, but very grievous and comes from a hardened and unrepentant heart, do not condemn him, but raise your eyes to the wondrous and incomprehensible judgments of God; then you will see that many people, formerly full of iniquity, later repented and reached a high degree of sanctity, and that, on the other hand, others, who were on a high level of perfection, fell into a deep abyss. Take care, lest you also suffer this calamity through judging others.
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.
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.