He who devoutly strives to attain wisdom and is on his guard against the invisible powers, should pray that both natural discrimination - whose light is but limited - and the illuminating grace of the Spirit abide in him. The first by means of practice trains the flesh in virtue, the second illuminates the intellect so that it chooses above all else companionship with wisdom; and through wisdom it destroys the strongholds of evil and pulls down 'all the self-esteem that exalts itself against the knowledge of God' (II Cor. 10:5).
Maximus the ConfessorThe man who has struggled bravely with the passions of the body, has fought ably against unclean spirits, and has expelled from his soul the conceptual images they provoke, should pray for a pure heart to be given him and for a spirit of integrity to be renewed within him (cf. Ps. 51:10). In other words, he should pray that by grace he may be completely emptied of evil thoughts and filled with divine thoughts, so that he may become a spiritual world of God, splendid and vast, wrought from moral, natural and theological forms of contemplation.
Maximus the ConfessorJust as the light of the sun attracts a healthy eye, so through love knowledge of God naturally draws to itself a pure intellect.
Maximus the Confessor...the Lord said as He drew near His passion, 'Now is the Son of man glorified, and God is glorified in Him. If God is glorified in Him, God will also glorify Him in Himself; and He will glorify Him at once' (Jn. 13:31-32). From This it is clear that divine gifts follow sufferings endured for the sake of virtue.
Maximus the ConfessorHe who is a beginner on the way must not be brought to practise the commandments by kindness alone, but must more often be induced to continue the struggle by being rigorously reminded of God's judgment. In this way he will not only be moved by love to desire what is divine, but will be moved by fear to avoid what is evil. For 'I will sing to Thee, O Lord, of mercy and judgment' (Ps. 101:1 LXX). He will sing to God charmed by love, and steeled by fear he will have strength for the song.
Maximus the Confessor