Those who meditate unceasingly upon the holy and glorious name [of Jesus] in the depths of their heart can sometimes see the radiance of their own spirit-intelligence. For when the mind is profoundly concentrated on this invocation, we feel experientially how it starts burning off all the layers of dirt that normally suffocates the soul.
Almsgiving heals the soul's incensive power; fasting withers sensual desire; prayer purifies the intellect and prepares it for contemplation of created beings. For the Lord has given us commandments which correspond to the powers of the soul.
The roof of any house stands upon the foundations and the rest of the structure. The foundations themselves are laid in order to carry the roof. This is both useful and necessary, for the roof cannot stand without the foundations and the foundations are absolutely useless without the roof-- no help to any living creature. In the same way the grace of God is preserved by the practice of the commandments, and the observance of these commandments is laid down like foundations through the gift of God. The grace of the Spirit cannot remain with us without the practice of the commandments, but the practice of the commandments is of no help or advantage to us without the grace of God.
If you are a friend of Christ you should have as friends persons who are of benefit to you and contribute to your way of life. Let your friends be men of peace, spiritual brethren, holy fathers. It is of such that our Lord was speaking when He said: 'My mother and brethren are those who do the will of My Father who is in heaven.' (cf. Matt. 12:49-50).