The Spirit does not take up His abode in someone’s life through a physical approach; how could a corporeal being approach the Bodiless one? Instead, the Spirit comes to us when we withdraw ourselves from evil passions, which have crept into the soul through its friendship with the flesh, alienating us from a close relationship with God. Only when a man has been cleansed from the shame of his evil, and has returned to his natural beauty, and the original form of the Royal Image has been restored in him, is it possible for him to approach the Paraclete. Then, like the sun, He will show you in Himself the image of the invisible, and with purified eyes you will see the image of the invisible, and with purified eyes you will see in this blessed image the unspeakable beauty of its prototype. Through Him hearts are lifted up, the infirm are held by the hand, and those who who progress are brought to perfection. He shines upon those who are cleansed from every spot, and makes them spiritual men through fellowship with Himself. So too Spirit-bearing souls, illumined by Him, finally become spiritual themselves, and their grace is sent forth to others. From this comes knowledge of the future, understanding of mysteries, apprehension of hidden things, distribution of wonderful gifts, heavenly citizenship, a place in the choir of angels, endless joy in the presence of God, becoming like God, and, the highest of all desires, becoming God.
St. Basil the Great, On the Holy Spirit, ch. 9