Jesus’ kingdom has been expanding, with people from across the Mediterranean world entering into it. Yet suddenly we meet a group who seem anachronistic – part of a much earlier stage in the story of Jesus. So why are they here in our verses?
To make sense of this, start with baptism. As both Peter (Ac 2:38) and John the Baptist (Lu 3:3) preached, baptism links to repentance: it’s a sign that a person is admitting their sins and wanting to wash them away. But it’s much more than that too. John did his baptising in the River Jordan. This was the river which Israel crossed to gain her promised land (Jos 3:17); John took the people back to their origins. Why? Because sinful Israel needed to be reborn. Hence, Jesus went into the water with the people (Mt 3:13-15). He had no personal sin but was willing to join them as their king who would die to save them. Baptism has both an individual and a group aspect.
With that in mind, now think of baptism in the Spirit. John said that though he baptised with water, Jesus would baptise with the Spirit and fire (Lu 3:16). John imagined a greater river flowing through the land, a river full of the very life of God – the Holy Spirit – and Jesus would plunge his people into that. But unlike water baptism, they would not leave the river again. From then on they would live their lives – individually and as a group – in this greater river; they would live their lives in the Spirit, even ‘drinking’ the river so that they were filled with the Spirit (1Co 12:13). This baptism, therefore, creates powerful unity between Christians as the Spirit flows around and between us, joining us as one. Becoming a member of a local church is a visible expression of this invisible reality.
But how does Jesus perform this baptism in the Spirit? In general, the Bible links it to conversion. When a person turns to Christ in repentance and is baptised, they also receive the Holy Spirit at the same time (Ac 2:38); all Christians are filled with the Spirit (Ep4:3-6). When some teach that baptism in the Spirit is a later experience in a believer’s life, they are mistaken. However, Jesus also used three historical events to show the giving of the Spirit: one-off, visible baptisms in the Spirit. The first was on the day of Pentecost, when the Spirit filled a house and Jewish believers were touched by fire and spoke in tongues (Ac 2:2-4). The second was in Samaria, to show Jesus expanding his kingdom to welcome in half-Jews (Ac 8:17). The third was in Caesaria, to show Jesus making his kingdom truly international as Gentiles entered into the Spirit too (Ac 10:44-46). And once those three, one-offs, visible events had occurred, the church was truly ready to burst out of the borders of ancient Israel, and travel out into the nations.
Which brings us back to our verses. Paul is, here, far away on the western coast of Asia (Turkey). Having toured some of his old churches, he’s now ready to spend time in the city of Ephesus (v1, see also Ac 18:20). Here he meets some disciples who know about the Lord but not about the Spirit (v2). This strange anomaly has come about because they only know the preparatory teaching and baptism of John (v3); they don’t have a personal faith in Jesus. How this group have managed to end up in Ephesus, we do not know. But in the Lord’s providence it is very suitable that they should meet Paul here, as a sign to him of the next phase of his work. Old Israel is dying and Paul knows he must make a final journey to Jerusalem, to testify to the people of the close judgement and show the Lord’s work among the Gentiles (see the previous Acts sermon). Paul will follow in Jesus’ footsteps, including suffering in the city. So to meet John the Baptist – albeit through his disciples – at this point, is a nice reflection of the Lord’s own ministry, which began with John (Mk 1:4). Not only that, Jesus’ apostle will complete John’s work by seeing John’s 12 ‘apostles’ (v12) converted (v4,5). So the Lord marks this special moment with a visible baptism in the Spirit, as John’s disciples wade, at last, into the river of the Spirit (v6). And John can now rest in peace (cf Mt 11:3). It’s a lovely ending to John’s story and a reminder to us that our life stories are never over, until the Lord writes the final chapter and, often, it can surprise us!