Romans 8:9: " But ye are not in the flesh; if so be that the Spirit of God dwell in you."
The Spirit of God dwells in all believers: those who are "in Christ Jesus." There is no phrase more frequently employed in the New Testament than this phrase. To have within us the Spirit who also belongs to Christ is the same as to have Christ Himself. ( Verse 10; Eph. 3:17) This is the normal Christian state (of being).
Paul gives the criterion by which we may easily determine whether we are "in spirit" or still "in flesh"...whether God's Spirit is dwelling in us. It is not said here that Christ is with His people, or at their hand, but they are in Him and He in them. "Dwell" in you must not be diluted to dwelleth among you. The passage is sometimes used in that sense. " If any man have not a Christ-like spirit, he is none of His." This is sound Scripturally; for the object of the Spirit of Christ dwelling in us is to make our spirit like that of Christ's. But it is the personal Spirit of Christ that is meant here, and not a disposition like Christ's.
Christ has come, not merely in the way of gifts, or of influences, or of operations, as He came to the prophets, for then Christ's going away would be a loss, and not a gain. Then the Spirit's presence would be a mere pledge and not an earnest; but He comes to us as Christ came by a real and personal visitation. (Rom. 8:9-11; 1 Cor. 6:19; 2 Cor. 6:16; 8:16)
The indwelling is mentioned throughout the Scriptures and is expressed in a variety of figures. Here it is that of a house or a temple. The Spirit, being its owner and inhabitant, makes it a fit habitation for Himself. He adorns it. He uses it for Himself. Since God's Spirit is the absolute opposite of the old sin power, it is easy to tell who dwells in the house of your heart. Those who live in the flesh do not want to have the Spirit. They do not belong to Him.
In Romans 7: 17-18,20 it was the indwelling sin that ruled but now it is the indwelling Spirit that rules.
In Romans 8: 10-11:
Those in Christ are clearly distinguished from those who remain under condemnation in the flesh:
That which gives being to a Christian is the Spirit of Christ dwelling in him. He is to a Christian what the soul is to a man. Consider what the body is without the soul. It is dead, defiled, and deformed. It is a piece of dust. When the Spirit of Christ enters, it has light and life in it. (Eph. 4:18)
So, Paul gives the clue as to how we can know if we are Christian - if His Spirit is dwelling in us. The heart in which God's Spirit dwells and hears and feels the Spirit's promptings is moved to follow that prompting by the power which the Spirit supplies. The Spirit is present in His Word, and we hear Him in our hearts when His Word is in us and moves us. Only in and through His Word does His Spirit dwell in us, speak to us, impel us, and control us. This excludes all autosuggestion; all hearing of fictitious, imaginary inward voices. We have the written Word with which to test every inward Word that we have absorbed. So, the proof is to see whether God's Spirit is dwelling within.
Now when the Spirit of Christ enters into this vile, dead, and decaying body, He creates a new light and a new life within us. He makes all things new. And as the Spirit enlightens; He also enlivens. He kindles a holy fire within. He makes our Christian souls move willingly toward God. He reforms us daily, constantly by casting out all those worldly beasts that lodged in us, and all those unruly affections that controlled us and cleared out idols that defiled His temple.
We are temples of the Holy Spirit. We have God in our hearts. He is the owner of our souls. He is our life. He is our peace. He is our happiness. Tenants never care for the house like the owner. Tenants often wreck and ruin the house and allow things to go to pieces. But owners are always repairing. When the Devil held our hearts, all of us were out of whack; ignorance ruled our minds; there was rebellion in the will; disorder in the affections; and death reigned in the soul.
But the coming of the Holy Spirit brings life and light.
Those who are in Christ would not defile this temple. So, we must not bring defiling thoughts into our souls... When we do, we bring them into the presence of God.
His indwelling is constant and eternal. We will never be separated from Him. (John 14:16; Rom. 8:35f.)
" Hereby we know that we dwell in Him, and He in us, because He hath given us of His Spirit." (1 John 4:13)
This indwelling of the Spirit is sure evidence of a renewed state.
We as believers should be careful not to grieve the Spirit.
We must abide constantly in His wonderful presence.