Taken from "Filled Unto All the Fullness of God" by T. Austin-Sparks:
FOUR FACTS CONCERNING THE HOLY SPIRIT
In the first place we have the facts concerning the Holy Spirit as to the life of the believer, and in two passages we are told of the initial act of the Holy Spirit when faith in the Lord Jesus has been exercised. That act is
1. The Sealing of the Spirit
Ephesians 1:13: "In whom you also, having heard the word of the truth, the gospel of your salvation, in whom, having also believed, you were sealed with the Holy Spirit of promise".
There is a fact: you were sealed when you believed, and the seal was the gift of the Holy Spirit Himself. That is not only something done and finished; it secures everything else, as implied by the last clause: "the Holy Spirit of promise". That points on to the inheritance. Ephesians 4:30: "And grieve not the Holy Spirit of God, in whom you were sealed unto the day of redemption".
The first fact, then, is the sealing of the Spirit, by which we are made God's spiritual people.
2. Introduction into the Presence of God
Ephesians 2:18: "For through Him we both have our access in one Spirit unto the Father".
That clearly says that we are introduced into the presence of the Father by the Spirit. "They that worship Him must worship in spirit and truth"; "God is a Spirit". The Lord put those words over against the formal, traditional worship in Mount Gerizim and in Jerusalem, and implied that in neither of those places was there really a genuine coming into the presence of God. It was historic worship, and as for coming into the presence of God, that was quite another thing. Now the question is of coming right into fellowship with God, and that is in spirit and in truth, representing a spiritual state. The spiritual state is essential for the presence of God, and that is represented by the Holy Spirit Himself being in possession, to bring us into living fellowship with the Father.
3. The Indwelling of the Spirit
The third fact is in the same chapter, Ephesians 2:22: "In whom you also are built together for a habitation of God in the Spirit".
The church is the dwelling place of God in the Spirit; God the Holy Spirit dwelling in the church, the Body of Christ; thus making this a spiritual building, a spiritual habitation, a spiritual Body, a spiritual church; defining quite clearly what the church is - a spiritual thing by reason of the Holy Spirit indwelling.
4. Revelation by the Holy Spirit
Ephesians 3:5: "Which in other generations was not made known unto the sons of men, as it has now been revealed unto His holy apostles and prophets in the Spirit".
Revelation by the Spirit is a constituent of the Body of Christ, the Lord's people. They are made a spiritual people because they have spiritual revelation. Something which has been reserved for revelation unto and by the Body of Christ, hidden - there, but unrevealed. But now the Body, the vessel, has been brought into being, unto which that secret was reserved, and the Holy Spirit is the Revealer of the secret. It is because of the nature and fact of that revelation that the church is a spiritual Body. The passage in chapter 1 verse 17 corresponds with that:
"That the God of our Lord Jesus Christ, the Father of glory, may give unto you a spirit of wisdom and revelation in the knowledge of Him".
The Revised Version uses a small "s" for "spirit" there, by which the revisers intend to imply that it is not the Holy Spirit that is being spoken of, but it is quite open to question as to whether such wisdom and revelation can be had apart from the Holy Spirit.
These are the four facts concerning the Holy Spirit in this letter, which make for spirituality.