He who always concentrates on the inner life will acquire self-restraint. He will also be able to contemplate, theologize, and pray. This is what the Apostle meant when he said: ‘Walk in the Spirit, and you will not fulfill the desire of the flesh’ (Gal. 5:16).
He who has renounced such things as marriage, possessions, and other worldly pursuits is outwardly a monk, but may not yet be a monk inwardly. Only he who has renounced the impassioned thoughts of his inner self, which is the intellect, is a true monk. It is easy to be a monk in one’s outer self if one wants to be; but no small struggle is required to be a monk in one’s inner self.
Who in this generation is completely free from impassioned thoughts and has been granted uninterrupted, pure, and spiritual prayer? Yet this is the mark of the inner monk.
Wishing to show that to fulfill every commandment is a duty, whereas sonship is a gift given to men through His own Blood, the Lord said, ‘When you have done all that is commanded you, say: “We are useless servants: we have only done what was our duty”’ (Luke 17:10). Thus the kingdom of heaven is not a reward for works, but a gift of grace prepared by the Master for His faithful servants. A slave does not demand his freedom as a reward: but he gives thanks as one who is in debt, and he receives freedom as a gift.