The12apostles were, of course, the divinely appointed leaders of the Christians (ch1). It was natural and proper, therefore, that they should send representative apostles to investigate the Samaritans" response to the gospel. This was especially important in view of the hostility that existed between the Hebrews and the Samaritans. The way the Jews and the Samaritans felt about one another is similar to how most Israelis and Palestinians feel about one another today. It was important that both the Samaritan Christians and the Jewish Christians believe that God had united them in Christ. When Peter and John came down, they observed that these Samaritans also had accepted Jesus as the Messiah. They asked God in prayer to send His Holy Spirit to baptize them as He had baptized the Jews who believed in Jesus (cf. Luke 11:13). [source][source][source]
"Being baptized "into" [1] . . . the name denotes incorporation into the Lord and his community, declaring one"s allegiance and implying the Lord"s ownership . . ." [2][source]
"This was a period of transition from the OT dispensation to the NT era, and these believers at Samaria were in a position similar to the believers at Jerusalem prior to Pentecost." [3][source]
However this baptism of the Spirit occurred somewhat differently than it had in Jerusalem (ch2; cf. Acts 8:38; Acts 10:44). There it happened spontaneously, but here it came in answer to the apostles" prayer and with the laying on of their hands. There the sound of a mighty wind, visible flames of fire, and speaking in tongues accompanied it. Here there is no mention that these phenomena were present. Perhaps tongues were not spoken here, if they were not, because the Jews and the Samaritans spoke the same language. In both places, Jerusalem and Samaria, the Spirit"s reception for permanent indwelling through Spirit baptism is in view, and the Holy Spirit baptized people who were already believers in Jesus Christ. [source][source][source]
"But what if the Spirit had come upon them [4] at their baptism when administrated by Philip? Undoubtedly what feelings there were against Philip and the Hellenists would have carried over to them, and they would have been doubly under suspicion. But God in his providence withheld the gift of the Holy Spirit till Peter and John laid their hands on the Samaritans-Peter and John , two leading apostles who were highly thought of in the mother church at Jerusalem and who would have been accepted at that time as brothers in Christ by the new converts in Samaria." [5][source]
Does what happened in Jerusalem and Samaria set a precedent for a "second blessing" experience (i.e, the baptism of the Spirit as a separate work of God subsequent to regeneration)? Paul described normative Spirit baptism in 1 Corinthians 12:13 and Romans 8:9. The person who has not experienced Spirit baptism is not a Christian ( Romans 8:9). Therefore the instances of Spirit baptism in Acts when it followed salvation later must have been exceptional occasions. This unusual separation of salvation and Spirit baptism is understandable. People needed to perceive Spirit baptism as such at the beginning of the church"s history. God baptized believers with the Spirit in this way to validate Jesus" promise that He would send the Spirit to indwell believers permanently, something not true previously ( John 14:16; John 14:26; John 15:26; John 16:7). [6][source]
In chapter2God identified Spirit baptism-which normally takes place without the believer being aware that it is happening-with wind, fire, and speaking in tongues. These things served as signs to the Jews present of God"s working. Here in chapter8 signs apparently did not announce the baptism of the Spirit but accompanied Philip"s preaching. What would have impressed the Samaritans that the baptism of the Spirit was taking place? And what would have impressed the Jews in Jerusalem that it had taken place in Samaria? The Spirit"s baptizing work taking place in response to the laying on of the apostles" hands would have done so (cf. Acts 9:17; Acts 19:6). This Isaiah , of course, exactly what happened. [source][source][source]
"Peter used the keys committed to him ( Matthew 16:18-19) to open the door officially to the Samaritans, just as he did to3 ,000 Jews at Pentecost, and would again a little later to the gentiles at the house of Cornelius (chap10). It would be a great mistake, however, to treat this incident at Samaria as normative for all subsequent believers. A look at the Spirit"s coming upon Saul ( Acts 9:17) and Cornelius ( Acts 10:44) will reveal considerable differences, so that the Samaritan experience was not the regular pattern in the Book of Acts." [7][source]