The Spirit's Work in Salvation
How the Spirit applies salvation to the believer: new birth, indwelling, sealing, adoption, the baptism into one body, and the filling of the Spirit
1. What the Spirit Does in the One Who Receives Him
In the last unit we saw the Spirit poured out on all flesh at Pentecost, given freely to everyone who turns to Christ. Now we ask a closer question: what does the Spirit do in the one who receives Him? The answer is breathtaking. The Spirit does not merely visit the believer or assist him from the outside; He gives new life, takes up residence within, marks the believer as God's own, assures him that he is a child of God, joins him to the body of Christ, and fills him for holy living. We will take these one at a time, for every one of them is the Spirit's work and not our own, the free gift of God to all who believe. What the Old Testament longed for and Pentecost began, the Spirit now does in every heart that trusts the Lord Jesus, and He does it not partly but fully, not for a season but forever.
2. He Gives New Birth
The first and deepest work of the Spirit in salvation is the new birth. When Nicodemus came to Jesus by night, the Lord told him, "Unless one is born of water and the Spirit, he cannot enter the kingdom of God. That which is born of the flesh is flesh, and that which is born of the Spirit is spirit" (John 3:5-6). We do not give ourselves this birth any more than a baby gives itself its first birth; it is the Spirit who makes a dead soul alive. Paul says God "saved us, through the washing of regeneration and renewing of the Holy Spirit" (Titus 3:5). This birth is not the work of water baptism, as though a ceremony could make a sinner new; it is the cleansing, renewing work of the Spirit Himself, granting a new heart to one who could never produce it. This is why Jesus said to Nicodemus, "You must be born again" (John 3:7), and likened the new birth to the wind that blows where it wishes (John 3:8); we feel its effect though we cannot command its working. Apart from this work no one can see the kingdom of God.
3. He Comes to Dwell Within
The same Spirit who gives the new birth then comes to live within the one He has made alive. This is the very thing Ezekiel had promised, that God would put His Spirit within His people. Now it is fulfilled in every believer. Paul writes plainly, "if anyone does not have the Spirit of Christ, he is not His" (Romans 8:9). The indwelling Spirit is not the privilege of a few advanced Christians; He is the mark of belonging to Christ at all. Your body, says Paul, "is the temple of the Holy Spirit who is in you, whom you have from God" (1 Corinthians 6:19). The God of heaven has come to live inside ordinary believers. This is why the Christian life is not a matter of trying harder in our own strength, but of yielding to the One who already dwells within. Every believer, the weakest and the strongest alike, is a dwelling place of God by His Spirit.
4. He Seals Us as God's Own
The Spirit also seals the believer. Paul says that in Christ, "having believed, you were sealed with the Holy Spirit of promise, who is the guarantee of our inheritance" (Ephesians 1:13-14). In the ancient world a king pressed his signet ring into soft wax upon an important document, and that seal marked the paper as his own, under his authority and protection. So the Spirit Himself is God's mark upon the believer, declaring that we belong to Him. This is why Paul could call Him the One "by whom you were sealed for the day of redemption" (Ephesians 4:30). The seal is also a down payment, a guarantee that the full inheritance is surely coming. The Spirit we now possess is God's pledge that He will finish what He has begun and bring us safely home. A seal in those days meant two things at once, ownership and security: the document so marked belonged to the king and was safe under his authority. So the Spirit declares both that we are God's and that we are kept by God, until the day He claims His own.
5. He Assures Us We Are God's Children
The indwelling Spirit also brings the believer assurance. We do not have to wonder whether God has received us, for the Spirit Himself testifies that He has. Paul writes, "you received the Spirit of adoption by whom we cry out, 'Abba, Father.' The Spirit Himself bears witness with our spirit that we are children of God" (Romans 8:15-16). It is the Spirit who teaches a frightened sinner to call the holy God his Father. The word Abba is the tender, familiar name a child uses for his own father, and it is the Spirit who puts that word in our mouths, assuring the doubting heart that it truly belongs to God. This witness is one of the sweetest of His works, for it turns slaves into sons and fear into the confidence of a child who knows he is loved.
6. Baptized with the Spirit into One Body
Jesus had promised that His disciples would be baptized with the Holy Spirit, and on the day of Pentecost it came to pass. But this baptism is not the privilege of a special class of believers; it is true of every Christian. Paul says, "by one Spirit we were all baptized into one body... and have all been made to drink into one Spirit" (1 Corinthians 12:13). To be baptized with the Spirit is to be placed, at conversion, into the body of Christ, joined to the Lord and to all His people. Notice the word all: not some, but all who belong to Christ have been baptized by the one Spirit into the one body. This is a settled fact accomplished when we are saved, not a later experience reserved for a favored few. We need not seek some second blessing to make us fully Christ's, for if we are His at all, the one Spirit has already baptized us into His one body.
7. Be Filled with the Spirit
If the baptism with the Spirit happens once, the filling of the Spirit is meant to happen again and again. Paul commands, "do not be drunk with wine, in which is dissipation; but be filled with the Spirit" (Ephesians 5:18). It is a striking comparison. A man controlled by strong drink is ruled by it; his words and steps are no longer his own. The believer is to be that fully under the Spirit's control, not by wine but by surrender to God. The likeness runs all through Scripture: when Hannah prayed in deep earnestness, Eli thought she was drunk (1 Samuel 1:13-14), and when the Spirit fell at Pentecost the crowd said the believers were full of new wine (Acts 2:13-15). The Spirit-filled life can look like that to the watching world, overflowing and unashamed, glad in God beyond what mere wine could ever give. And we may be filled again and again, as the early disciples were, for those who had been filled at Pentecost were filled afresh when they prayed (Acts 4:31). Paul describes what the filled life looks like: it speaks and sings to the Lord, it gives thanks always, and it serves others in humility (Ephesians 5:19-21). To be filled is to be repeatedly yielded to the Spirit, letting Him fill what we daily empty before Him, so that He may govern our speech, our worship, and our walk.
8. The Question of Tongues and the Gifts Today
Wherever the Spirit's work is discussed, the question of tongues and the miraculous gifts arises, and we ought to speak of it plainly and with charity. At Pentecost the believers spoke in real languages, so that the gathered nations heard the gospel each in his own tongue. Paul wrote much about such gifts in his letters to Corinth, and there he laid down truths that should guide us. The gifts are distributed by the Spirit as He wills, and they are not the same for everyone; when Paul asks, "Do all speak with tongues?" (1 Corinthians 12:30), he plainly expects the answer to be no. He sets love above every gift, and he insists that whatever is done be done for the building up of the church and in good order. Sincere Christians differ on whether the sign-gifts continue today as they did at the first, or whether they served the founding age of the church and the completing of Scripture. Some hold that these gifts served to found the church and to confirm the apostles' message while the Scriptures were still being written, and so passed away when that work was complete; others believe they continue to this day. On this our churches must extend charity to one another and not divide over what Scripture does not make a test of fellowship. But all may agree on the tests the Spirit Himself gives: whatever is truly of the Spirit will exalt Christ as Lord, will accord with the Scriptures, and will be governed by love. We will look more closely at the gifts of the Spirit, and at love as the greatest of them all, near the end of this course.