SUNDAY MORNING WORSHIP SERVICE, 10 May 2026
Sermon Series: “The Acts of the Apostles” (#29)
Sermon Text: Acts 18:24-19:10
Main Points:
Introduction
I. The Spirit corrects incomplete understanding of the gospel
II. The Spirit completes true faith in Christ
III. The Spirit multiplies the gospel through faithful ministry
Conclusion
About three years ago, Miyun and I bought a small lemon tree seedling from Bunnings Warehouse. Over the years, it has grown steadily, and amazingly, from its second year, it already began bearing fruit. This year, to our surprise, it produced nine lemons altogether.
But there is one problem. The lemons seem to be smaller than normal ones. As I looked at the tree, I began wondering whether something was lacking – perhaps insufficient fertiliser, poor nutrients in the soul, or some deficiency I simply haven’t noticed yet. The tree is alive; it is growing; it is even bearing fruit. But something still does not seem great.
Now, whenever we notice something is lacking in a tree – or even more importantly, in someone we love – what do we do? We do not simply ignore it. We try to identify the problem and supply what is missing. If a tree lacks nutrients, we feed it properly. If a child needs help, guidance, or support, we gladly provide it because we want healthy growth and flourishing life.
That is very similar to what the Holy Spirit is doing in the passage before us today in Acts 18 and 19. In this passage, there are people who genuinely know something about God. Apollos is eloquent, knowledgeable, and passionate. The disciples in Ephesus are sincere and spiritually serious. But both lack something essential. Their understanding of Jesus Christ and His saving work is incomplete.
And that’s a dangerous condition. One of the great dangers in the Christian life is not outright rejection of the gospel, but receiving it only partially. Equally dangerous is to remain in that partial knowledge. A person may know much about God, speak passionately about spiritual things, even live morally and sincerely, yet still not fully understand Christ and His saving work. That is exactly the situation we encounter in this passage.
Here, Luke shows us the Holy Spirit at work – not merely through dramatic signs, but through the faithful correction, completion, and multiplication of the gospel. The Spirit will not allow Christ to be misunderstood, minimised, or reduced to mere religious knowledge. He leads people into the fullness of the gospel and, then, sends them out so that the gospel spreads further.
The central concern of this passage is this: when the Holy Spirit brings God’s people into a full and right understanding of the gospel, the church is strengthened, believers are established, and the Word of God advances powerfully.
I. The Spirit Corrects Incomplete Understanding of the Gospel (18:24-28)
Acts introduces us to Apollos, a remarkably gifted man. He was eloquent, competent in the Scriptures, fervent in spirit, and bold in teaching. Humanly speaking, he looked like the ideal preacher and ministry worker.
But, Luke quietly exposes a serious deficiency: Apollos “knew only the baptism of John” (18:25). He understood repentance and preparation, but not yet the fullness of Christ’s completed work and the coming of the Holy Spirit at Pentecost.
That detail matters because sincerity alone is not enough. Zeal is not enough. Biblical literacy is not enough. A person may speak accurately about many things, and still possess an incomplete understanding of the gospel itself. In other words, he may recount Jesus’ death on the cross and His resurrection on the third day, but fail to grasp the meaning of Jesus’ substitutionary work – how Christ actually bears and removes sin. And where that remains unclear, he does not truly rely on Jesus as Saviour nor submit to Him as Lord.
What is striking is how the Spirit corrects Apollos. Not publicly or harshly, but through faithful believers like Priscilla and Aquila who “explained to him the way of God more accurately” (18:26). The Spirit uses ordinary servants, patient teaching, and humble correction to make the gospel clear.
This reveals two important truths. First, the gospel must not be merely approximately right or partially correct. It must be rightly understood. Apollos knew only the baptism of John, not the cross and the empty tomb of Christ. The baptism of John was not a heresy, but neither was it a complete revelation of Christ’s redemption.
The difference between preparation for Christ and fulfillment in Christ is enormous. John’s baptism called people to repent – to turn from sin and acknowledge their desperate need for God’s mercy. It brought them to awareness of need, but not yet to the answer.
Jesus is the answer. He calls sinners not only to repent, but to faith in Him as the promised Saviour. And in His death and resurrection, He does not merely point to salvation – He actually accomplishes it, dealing fully and finally with sin.
Second, spiritual maturity requires humility. Apollos was gifted enough to teach others, yet humble enough to be corrected. Often the greatest obstacle to growth is not ignorance itself, but pride that resists correction. Again, this is the work of the Holy Spirit. The Spirit brought Apollos into a fuller and accurate understanding of the gospel.
The Spirit’s work is therefore doctrinal as well as experiential. He leads His people into truth. He makes Christ known accurately. Where the gospel is unclear, distorted, or incomplete, the Spirit works to make it right.
Once Apollos is corrected, he becomes even more useful. V. 28 says he powerfully refuted the Jews in public, proving from the Scriptures that Jesus was the Christ. Right understanding of the gospel strengthens witness – bringing clarity in proclamation and confidence in Christ.
II. The Spirit Completes True Faith in Christ (19:1-7)
When Paul arrives in Ephesus, he encounters some disciples and immediately asks a penetrating question: “Did you receive the Holy Spirit when you believed?” (19:2). Their answer exposes the problem: they had not even heard that the Holy Spirit had been given. Again, this is not outright pagan unbelief. These men were religious and responsive. But, their faith remained incomplete because it had not yet fully grasped Jesus Christ crucified, risen, and reigning.
Paul explains that John’s baptism was preparatory. John pointed people beyond himself to Christ. True faith must rest not in repentance alone, but in Jesus Himself – that is, knowing Him as Saviour and following Him as Lord. Then these disciples are baptised in Jesus’ name, and the Holy Spirit comes upon them.
This happened because these men had not yet come to know Jesus as the promised Messiah who had been crucified and risen from the dead. They were still standing at the stage of John the Baptist’s ministry, looking forward to the coming Saviour. But now, through Paul’s preaching, they’re brought to Jesus Himself and receive the blessings of the new covenant through the Holy Spirit.
And Luke records this not merely as a historical transition in the early church, but as a reminder to every generation of believers of an important truth. It is possible to possess religious seriousness without truly knowing Christ. People may admire Jesus, respect Christian morality, or practice repentance, yet never rest in Christ’s finished work, nor know the life-giving presence of the Holy Spirit. The Holy Spirit does not merely improve religious people; He unites sinners to the risen Christ, transforming both their minds and their lives.
By transforming both their minds and lives, I mean that the Spirit changes the way believers think, speak, love, forgive, endure, and live each day. No longer do they see this present world as their true home, but as pilgrims journeying toward Christ’s kingdom. No longer do they measure themselves by worldly standards, but increasingly desire the righteousness of Christ.
Their ambitions, values, and priorities begin to change. They learn to hate the sin they once excused, and pursue the holiness they once ignored. They begin to speak truthfully, love sacrificially, forgive patiently, and endure suffering with hope. Even in ordinary and unseen parts of life – in marriage, parenting, work, friendship, conflict, disappointment, and temptation – the Spirit gradually conforms them to the character of Christ. Although this transformation is often slow and imperfect, believers begin to see the Holy Spirit’s work over time. By God’s grace, today is holier than yesterday, and tomorrow they press on to grow even more into the likeness of Christ.
This is not mere religious improvement or outward morality. It is the Spirit uniting sinners to the risen Christ and producing the life of Christ within them, within us.
III. The Spirit Multiplies the Gospel Through Faithful Ministry (19:8-10)
After the gospel is corrected and true faith established, the result is multiplication. Paul begins preaching boldly in the synagogue for three months. Some respond, but others harden themselves and oppose ‘the Way.’ At that point, Paul moves to the hall of Tyrannus and continues teaching daily. We’re not exactly sure who Tyrannus was, but Paul used his lecture hall as a place for teaching and preaching Christ.
A borrowed lecture hall and the daily teaching of Scripture may not have looked impressive. But through this ordinary ministry, the gospel spread extraordinarily far. Hear what v. 10 states: “all the residents of Asia heard the word of the Lord, both Jews and Greeks.” That is astonishing. From one teaching ministry in Ephesus, the gospel spreads throughout the entire region.
Notice how the gospel spreads: not primarily through miracles, not clever strategies, or political influence, but through the steady and faithful proclamation of God’s Word. The Spirit multiplies the gospel through ordinary means faithfully exercised over time.
Compare this with many modern ideas about church growth. Often people assume that gospel growth depends on novelty, charisma, influence, or visible success. But the book of Acts repeatedly emphasises something very different – that is, the Spirit works powerfully through the steady proclamation of Christ. No wonder Paul says in 1 Cor. 1:21 that God was pleased to save those who believe “through the folly of what we preach.” What appears weak and unimpressive in the eyes of the world becomes, by the Spirit’s power, the very means through which God saves sinners. That is why gathering each Lord’s Day matters so deeply. It is there that God’s Word is read and faithfully expounded, and through it the Spirit continues His work in His people.
There is also a progression across the whole passage: it says, first, Apollos is corrected; second, the Ephesian disciples are completed in Christ; and third, the Word spreads outward to the nations. That is how the Spirit ordinarily builds the church. He clarifies the gospel, establishes believers in Christ, and then advances the gospel through faithful ministry.
Conclusion
So, today’s passage reminds us that the church must constantly seek to have the gospel made right.
Some need correction because their understanding of Christ is incomplete. Others need completion because they possess religion without the fullness of faith in Jesus. And all believers are called to participate in the multiplication of the gospel through faithful ministry.
The encouraging truth in this passage is that the Spirit is committed to this work. He patiently corrects error, leads people fully to Christ, and causes the Word of God to spread far beyond what human strength could accomplish.
Therefore, the health and power of the church do not ultimately depend on human brilliance, personality, or innovation. They depend on the Spirit of God making Christ rightly known. And wherever Christ is rightly known, rightly believed, and faithfully proclaimed, the gospel will continue to bear fruit. And as the gospel continues to bear fruit, believers rejoice because such fruit is clear evidence of the Holy Spirit at work in and through us, His people. ***
St Columba's Presbyterian Church 