What does it mean to be as wise as a serpent? When a serpent is attacked, it is willing to have much of its body severed, as long as it saves the head. So to be wise as a serpent means to be willing to lose everything - your wealth, your reputation, your friends - as long as you save your faith. Your faith is your head, by which you learn all truth; and by that truth your soul is set free. We should, however, recognize that the wisdom of the serpent is not enough; we must be honest and innocent as doves. Indeed it is the combination of wisdom and innocence that creates virtue. The person who is wise as a serpent can sustain the most terrible attacks and still continue to flourish as a disciple of Christ. The person who is innocent refuses to retaliate against those who make the attacks. To be as innocent as a dove means never to take revenge on those who wrong you or undermine you. Unless wisdom is tempered by innocence, one attack provokes another, and conflict continues without end. Unless innocence is tempered by wisdom, a person is so vulnerable that he will not even survive a single attack. Rest assured that no one can ever take away your faith; your wisdom guards against that. But be careful never to bear a grudge against anyone who does you wrong.
Charity, temperance, contemplation, and prayer please God; gluttony, licentiousness, and what multiplies them, please the flesh. Therefore they who are in the flesh cannot please God. And they that are Christ’s have crucified their flesh with the passions and concupiscences.
Everything must be directed towards acquiring the Kingdom of God and fulfilling Christ's Gospel. True Christianity does not consist in intellectual abstract deliberations and teachings; rather, it is incarnate in life itself. Christ descended to earth not to instruct people in new forms of knowledge, but to call them to a new life. During our earthly life we prepare ourselves for eternity.
In order not to be in daily bondage to the passions and the Devil, you must set yourself an object to aim at, have this object constantly in view, and endeavor to attain it, conquering all obstacles by the name of the Lord. What is this object? The Kingdom of God, the Divine palace of glory, prepared for believers from the creation of the world. But as this object can only be attained by certain means, it also is necessary to have such means at one's disposal. And what are these means? Faith, hope, and love, especially the last. Believe, hope, and love, especially love, disregarding all obstacles; love God above everything and your neighbor as yourself. If you have not sufficient strength to preserve in your heart these inestimable treasures, fall down oftener at the feet of the God of Love. 'Ask, and it shall be given you; seek, and ye shall find; knock, and it shall be opened unto you' (Matt. 7:7-8) - for He Who has promised is true.
When the flesh flourishes, the soul fades; when the flesh has full liberty, the soul is straitened; when the flesh is satiated, the soul hungers; when the flesh is adorned, the soul is deformed; when the flesh overflows with laughter, the soul is surrounded by misfortune; when the flesh is in the light, the soul is in darkness...
To be a righteous man among the righteous is a great and praiseworthy thing. But it is a far greater and more praiseworthy thing to be a righteous man among the unrighteous.
Having guarded ourselves against distractions and worries, let us turn our attention to our body on which mental vigilance is completely dependent. Human bodies differ widely from one another in strength and health. Some by their strength are like copper and iron; others are frail like grass. For this reason everyone should rule his body with great prudence, after exploring his physical powers. For a strong and healthy body, special fasts and vigils are suitable; they make it lighter, and give the mind a special wakefulness. A weak body should be strengthened by food and sleep according to one's physical needs, but on no account to satiety. Satiety is extremely harmful even for a weak body; it weakens it, and makes it susceptible to disease. Wise temperance of the stomach is a door to all the virtues. Restrain the stomach, and you will enter Paradise. But if you please and pamper your stomach, you will hurl yourself over the precipice of bodily impurity, into the fire of wrath and fury, you will coarsen and darken your mind, and in this way you will ruin your powers of attention and self-control, your sobriety and vigilance…