Here is the second section of a sample chapter for a possible proposal I'm thinking of making, Generous Ecclesiology.
So baptism in water was the most concrete way of telling whether a person was presumed “in” or “out” of the early church. Certainly attendance at a local assembly of believers pointed in this direction as well, although we can imagine un-baptized individuals being present in a local “church” who would not yet have been considered fully “in.” However, at the same time that baptism played this visible role, the early church soon conceptualized an even more important, underlying element in the entrance equation. What about someone who did not believe Jesus was the messiah but who had been baptized by John the Baptist? Were they “in” or “out”? At some point, at least some Christians came to conclude that such individuals were “out,” even though they were baptized almost exactly like the followers of Jesus. The difference was that these individuals did not have the Holy Spirit, which only could come through Jesus, not John the Baptist.
The portrayal of the Day of Pentecost in Acts 2 gives us an excellent picture of this understanding. The disciples have been told to wait in Jerusalem for the promised coming of the Holy Spirit (Acts 1:4-5). John the Baptist baptized in water, but Jesus will baptize with Holy Spirit (Luke 3:16).[i] So on the Day of Pentecost, those who have believed in Jesus’ resurrection are gathered together and are “filled” with the Holy Spirit (Acts 2:1-4), also called receiving the Spirit (2:38) or being “baptized” with the Holy Spirit (1:5). In Luke-Acts, this event is part of the commencement of the “last days” foretold by the prophet Joel, the age at the end of which God would restore Israel and establish his kingdom once and for all (e.g., Luke 1:68; 21:24).
Throughout the book of Acts, the coming of the Holy Spirit is the essential moment in “conversion,” as we have seen, more crucial even than baptism. If we are to use this word, conversion, we must make it very clear that—at least in the case of Jewish “converts”—we are not speaking of a change from one religion to another. When we speak of “conversion” to the Way or into the body of Jesus followers, we are talking about joining a group that understood itself as nothing other than the truest people of Israel. Ethnic Israel and its basic categories remained the foundation on which the house of God’s “elect,” his “last days” kingdom people, was built. When Paul speaks of the Gentiles coming “in” to God’s people, he thinks of them being grafted into a tree whose natural branches remain ethnic Israel (cf. Rom. 11:17-24).
Nevertheless, as we keep these things in mind, the Holy Spirit is clearly the key element of conversion in Acts, whether one is a Jew or a Gentile. Two incidents we mentioned in the first part of the chapter make the point clear. In Acts 8, some Samaritans have believed and have been baptized, but they have not yet received the Holy Spirit (8:14-17). Peter and John lay hands on them so that they will receive this most crucial element in conversion. In the thought world of Acts, it does not matter that they have been baptized, indeed that they already believe (8:12-13). They are not “in” because they have not received the Spirit. Similarly, in Acts 10, the question of whether Cornelius and the Gentiles with him can be included in God’s people and baptized is made moot by the fact that God has already poured out the Holy Spirit on them. The question of the ritual act is settled by the fact that the reality it signifies has already taken place (cf. Acts 15:8-9).
When we move beyond the presentation of Luke-Acts, we find a very similar theology of the Holy Spirit in relation to becoming a true “child of God” and a true member of God’s people. Paul does not consider anyone—Jew or Gentile—to be one of the elect, a true descendant of Abraham, part of the body of Christ and a member of God’s true Israel, unless they have the Spirit. “If someone does not have the Spirit of Christ, this person does not belong to him” (Rom. 8:9). “As many as are led by the Spirit of God, these are sons of God” (8:14). “You have received the Spirit of adoption, by which we cry, ‘Abba, Father’” (8:15).
Similarly, Paul speaks of the Holy Spirit as the arrabōn of what is to come, God’s “seal” on us that shows he is our owner (2 Cor. 1:22; 5:5; cf. Eph. 1:13-14). An arrabōn was like the earnest money someone puts down on a house. It is both a guarantee that makes it clear you are going to buy the house and a deposit toward buying the house. The sense is thus that the Holy Spirit is both a guarantee that believers will receive the inheritance of the kingdom, while providing a spiritual deposit of what that kingdom will be like. When we compare what Paul has to say about the Spirit with what he has to say in his writings about water baptism, there is simply no comparison. The Spirit is the primary element.
The anonymous book of Hebrews similarly presupposes that true membership among the descendants of Abraham (cf. 2:16) entails partaking and tasting of the Holy Spirit (6:4-5). We should not think of such tasting as merely dabbling any more than Jesus “tasting” death was a mere flirtation with death (2:9). As problematic as Hebrews 6:4-8 may be to us, we can be sure that Hebrews understands those who fall away at one time to have been full members of God’s people.
But what did this experience look like, and what would it then look like today? In Acts, the coming of the Spirit is frequently depicted in dramatic terms, with miracles and tongues often accompanying. Paul and Hebrews also imply that wonders often served as ratification of the Spirit’s presence (e.g., Gal. 3:1-5; 2 Cor. 12:12; Heb. 2:4). Are we to think, though, that everyone in the early church who was understood to have the Spirit experienced some dramatic manifestation of the Spirit’s coming? It does not seem likely. While we hear of many dramatic conversions, the New Testament is silent about such manifestations in relation to the vast majority of the early believers. Paul speaks of the Spirit witnessing with our Spirit that we are children of God (Rom. 8:16), which might imply only a calm sense of assurance.
When we ask today, almost two thousand years later, what receiving the Spirit might look like, at first the answer seems straightforward. Regardless of when you were baptized, you receive the Spirit after you repent of your sins and confess faith in Jesus as Lord. Thereafter the Spirit “fills” you—as God sees fit.[ii] Acts 2:38 captures this sense well when Peter tells the crowd on the Day of Pentecost, “Repent and let each of you be baptized in the name of Jesus Christ for the forgiveness of your sins, and you will receive the gift of the Holy Spirit.”
Although it is probably fair to say that most Christian traditions do not focus much on the Holy Spirit at all, we still find significant disagreements among different Christian groups on their official positions. For example, perhaps most Christian traditions associate the timing of the Spirit with the timing of baptism more closely than we would argue the New Testament would necessarily warrant. Although in many respects they are on opposite ends of the church spectrum, both the Roman Catholic Church and some forms of the Christian Church would so associate baptism with receiving the Spirit that one’s salvation is in deep trouble without it. The first baptizes infants, the second only adults, but both see baptism as essential to receiving the Spirit to where the soul of an un-baptized person is in serious danger regardless of any confession of faith they might have made.
The United Pentecostal Church is a fascinating example of a group that sees baptism as essential to getting in and links receiving the Spirit closely with baptism. But its real uniqueness comes in that it considers speaking in tongues the sign that a person has received the Spirit and insists that baptism can only take place in the name of Jesus alone, since this group does not believe in the Trinity. Thus a person who does not speak in tongues or who has not been baptized in this way has a dubious claim to be a Christian. Other Pentecostal and holiness groups have considered the Day of Pentecost a model not for conversion but for a second experience as a Christian. But even these groups usually have a place for receiving the Spirit in some sense at conversion as well.
The question of those Christian groups that baptize infants is a tricky one as well. Such groups usually associate receiving the Spirit officially with baptism, even though the child is obviously unable to make a confession of faith or repentance. Although the first impression of many is simply to dismiss this idea out of hand, we remember that in Luke 1:15 John the Baptist is filled with the Spirit even before he is born. Luke-Acts makes no clear distinction between this filling with the Spirit and the baptism with the Spirit in Acts 2. The clear implication is that the author of Luke does not see repentance and confession necessary for an unborn child to be filled with the Spirit. We thus cannot make a clear theological objection to the idea that baptized infants might receive the Spirit at that time, at least not biblically. Certainly it is biblical to expect that such a person will also need to appropriate Christ as Lord and as their means of atonement later in life.
When the smoke clears from the disagreements between different Christian traditions, we are still left with potential common ground. On the one hand, the absolute necessity that a person have the Holy Spirit in order to belong to God’s people remains. We also find the strong common sense of Christendom and the Bible that receiving the Holy Spirit is closely associated with baptism. It is appropriate for us to maintain this association as long as we do not insist that a person must be baptized to receive the Holy Spirit and recognize the need for a person to maintain the presence of the Holy Spirit to the end of one’s life. Whether a person was baptized as an infant or adult, the Spirit must nevertheless be present till death if one is to be "saved."
[i] The Gospel of John preserves this same thinking when Jesus says, “If I go away, I will send him [the Holy Spirit] to you” (John 16:7-11).
[ii] We remember that at Samaria the Spirit filling was not immediate and, theologically, we probably want to give God the final say as to when a person actually receives the Spirit, rather than making conversion a matter of some formula that we as mortals can effect whenever we want.