Ye are not in the flesh but in the Spirit if so be that the Spirit of God dwell in you. Now if any man have not the Spirit of Christ he is none of His — Rom 8:9
A spiritual man is not so much a man possessing a strong spiritual character as a man filled with the Holy Spirit. So the apostle said: Ye are not in the flesh, but in the Spirit, if so be that the Spirit of God dwelleth in you.
The glory of the new creation, then, is not only that it recreates the human spirit, but that it fits it for the abode of God Himself, and makes it dependent upon the sun, as the child upon the mother. The highest spirituality, therefore, is the most utter helplessness, the most entire dependence and the most complete possession of the Holy Spirit. Therefore, the beautiful act of Christ in breathing upon His disciples, and imparting to them from His own lips the very Spirit that was already in Him, expressed in the most vivid manner the crowning glory of the new creation. And when the Holy Spirit thus possesses us, He fills every part of our being.