To preserve inner peace:
(1) First of all keep your outer senses in order and flee all licentiousness in your external conduct, – namely, neither look, speak, gesticulate, walk nor do anything else with agitation, but always quietly and decorously. Accustomed to behave with decorous quietness in your external movements and actions, you will easily and without labour acquire peace within yourself, in the heart; for, according to the testimony of the fathers, the inner man takes his tone from the outer man.
(2) Be disposed to love all men and to live in accord with everyone, as St. Paul instructs: ‘If it be possible, as much as lieth in you, live peaceably with all men’ (Rom. xii. 18).
(3) Keep your conscience unstained, so that it does not gnaw at you or reproach you in anything, but is at peace in relation to God, to yourself, to your neighbours, and to all external things. If your conscience is thus kept clean, it will produce, deepen and strengthen inner peace, as David says: ‘Great peace have they which love thy law: and nothing shall offend them’ (Ps. cxix. 165).
(4) Accustom yourself to bear all unpleasantness and insults without perturbation. It is true that before you acquire this habit you will have to grieve and suffer much in your heart through lack of experience in controlling yourself in such cases. But once this habit is acquired, your soul will find great comfort in the very troubles you meet with. If you are resolute, you will day by day learn to manage yourself better and better and will soon reach a state when you will know how to preserve the peace of your spirit in all storms, both inner and outer.
If at times you are unable to manage your heart and restore peace in it by driving away all stress and griefs, have recourse to prayer and be persistent, imitating our Lord and Saviour, Who prayed three times in the garden of Gethsemane, to show you by His example that prayer should be your refuge in every stress and affliction of the heart and that, no matter how faint-hearted and grieved you may be, you should not abandon it until you reach a state when your will is in complete accord with the will of God and, calmed by this, your heart is filled with courageous daring and is joyfully ready to meet, accept and bear the very thing it feared and wished to avoid; just as our Lord felt fear, sorrow and grief, but, regaining peace through prayer, said calmly: ‘Rise, let us be going: behold, he is at hand that doth betray me’ (Matt. xxvi. 46).
Peace of Heart is Established Little by Little
Your constant care should be not to let your heart become agitated or troubled, but to use every effort to keep it peaceful and calm. Seeing your efforts and endeavours, God will send you His grace and will make your soul a city of peace. Then your heart will become the house of comfort as is allegorically expressed in the following Psalm: ‘Jerusalem is builded as a city’ (Ps. cxxii. 3). God has required only one thing from you, that every time you are disturbed by something, you should immediately restore peace in yourself, and should thus remain undisturbed in all your actions and occupations. You must know that this requires patience; for just as a city is not built in a day, you cannot expect to gain inner peace in a day. For gaining inner peace means building a house for the God of peace and a tabernacle for the Almighty, and in this way becoming a temple of God. You must also know that it is God Himself Who builds this house in you, and without Him all your labour will be in vain, as it is written: ‘Except the Lord build the house, they labour in vain that build it’ (Ps. cxxvii. 1). You must know too that the main foundation of this peace of heart is humility and avoidance of actions, works and occupations which bring worry and care. As regards the first – who does not know that humility, peace of heart and meekness are so closely related that where one is, the other is too. A man whose heart is at peace and who is meek is also humble, and a man who is humble in heart, is also meek and at peace. This is why our Lord joined them indissolubly together, saying: ‘Learn of me; for I am meek and lowly in heart’ (Matt. xi. 29). As regards the second, we see its prototype in the Old Testament, namely, in the fact that God wished His house to be built not by David, who spent almost all his life in wars and tribulations, but by his son Solomon, who, by his name, was a peaceful king and fought no one.