Prayer demands that the mind should be pure of all thought and should admit nothing not belonging to prayer, even if it were good in itself. As if inspired by God the mind should withdraw from all things and hold its converse with Him alone.
'Fear of the Lord is the beginning of wisdom' (Prov. 1:7). For where there is fear, there the commandments are kept, and where the commandments are kept the flesh is purified, together with the cloud that envelops the soul and prevents it from clearly seeing the divine radiance.
When a man walks in the fear of God he knows no fear, even if he were to be surrounded by wicked men. He has the fear of God within him and wears the invincible armor of faith. This makes him strong and able to take on anything, even things which seem difficult or impossible to most people. Such a man is like a giant surrounded by monkeys, or a roaring lion among dogs and foxes. He goes forward trusting in the Lord and the constancy of his will to strike and paralyze his foes. He wields the blazing club of the Word in wisdom.
Our holy fathers have renounced all other spiritual work and concentrated wholly on this one doing, that is, on guarding the heart, convinced that, through this practice, they would easily attain every other virtue, whereas without it not a single virtue can be firmly established.
If you want cure your soul, you need four things. The first is to forgive your enemies. The second is to confess thoroughly. The third is to blame yourself. The fourth is to resolve to sin no more. If we wish to be saved, we must always blame ourselves and not attribute our wrong acts to others. And God, Who is most compassionate, will forgive us.
'If our prayer is not in harmony with our deeds, we labor in vain,' Abba Moses often told the young monks. 'How are we to accomplish such harmony?' they asked him one day. 'When we make that which we seek fitting to our prayer,' explained the saint. 'Only then can the soul be reconciled with its Creator and its prayer be acceptable, when it sets aside all of its own evil intentions.'
A man who falls into sin is different from the way he was created. He is different, because he changes by his own actions the way he was meant to be. Man renounces himself when he becomes a different person through repentance. He leaves a corrupted man, which he had become through sin, and becomes such as he once was created, through mercy.