This answer relates only to the comprehensible tongues recorded in Acts. It does not relate to the incomprehensible tongues Paul mentions in 1 Corinthians 14.
2 For anyone who speaks in a tongue does not speak to people but to God. Indeed, no one understands them; they utter mysteries by the Spirit. (1 Corinthians 14:2 NIV)
This verse is confirmed several times later in the same chapter, but immediately it is clear that the Corinth tongues are not the same as the comprehensible tongues in Acts 2:8-10.
How many times did real tongues occur in Acts?
The three clear examples of comprehensible tongues are as follows:
Acts 2 – the initial Jewish baptisms at Pentecost marking the start of the international church outside Judea’s borders
Acts 2:8 Then how is it that each of us hears them in our native language? 9 Parthians, Medes and Elamites; residents of Mesopotamia, Judea and Cappadocia, Pontus and Asia,[b] 10 Phrygia and Pamphylia, Egypt and the parts of Libya near Cyrene; visitors from Rome 11 (both Jews and converts to Judaism); Cretans and Arabs—we hear them declaring the wonders of God in our own tongues!” (NIV)
Acts 10 – the first Gentile baptisms, at Caesarea
Acts 2:46 For they heard them speaking in tongues[b] and praising God. Then Peter said, 47 “Surely no one can stand in the way of their being baptized with water. They have received the Holy Spirit just as we have.” 48 So he ordered that they be baptized in the name of Jesus Christ. Then they asked Peter to stay with them for a few days. (NIV)
Peter confirms that these were comprehensible tongues in the next chapter:
Acts 11:15 “As I began to speak, the Holy Spirit came on them as he had come on us at the beginning.
Acts 19 = the first rebaptisms, at Ephesus
Acts 19:4 Paul said, “John’s baptism was a baptism of repentance. He told the people to believe in the one coming after him, that is, in Jesus.” 5 On hearing this, they were baptized in the name of the Lord Jesus. 6 When Paul placed his hands on them, the Holy Spirit came on them, and they spoke in tongues and prophesied. 7 There were about twelve men in all.
However, while not explicitly stated it seems likely that the first Samaritan baptisms in Acts 8 also spoke in (real language) tongues?
It is often note that there are only 3 incidents of “tongues” (real languages, not modern Pentecostal glossolalia) in the Book of Acts, and that each time they happen when a new type/group/category of people are baptized: Acts 2, 10, 19. …. but by the same reasoning it could be that there was another 4th incident of “tongues” in Acts 8,when the first Samaritans were baptized.
Acts 8 doesn’t specifically say *how* the powers of the spirit were poured out on that occasion. But it doesn’t say that they weren’t or say that any other gift was. So, if the tongues are a sign of expanding the baptism circle it would help Peter’s argument for Cornelius if the first Samaritan baptisms had the same tongues as went with the first Pentecost baptisms, Gentile baptisms and Rebaptisms.
Acts 8:14 When the apostles in Jerusalem heard that Samaria had accepted the word of God, they sent Peter and John to Samaria. 15 When they arrived, they prayed for the new believers there that they might receive the Holy Spirit, 16 because the Holy Spirit had not yet come on any of them; they had simply been baptized in the name of the Lord Jesus. 17 Then Peter and John placed their hands on them, and they received the Holy Spirit. 18 When Simon saw that the Spirit was given at the laying on of the apostles’ hands, he offered them money 19 and said, “Give me also this ability so that everyone on whom I lay my hands may receive the Holy Spirit.” (NIV)
Clearly the language here is the same as the other 3 incidents in Acts, except that “tongues” are not specifically mentioned. But it is difficult to see what else Simon could have seen and heard other than comprehensible languages. The only alternative would be sudden healings of people – which Luke would surely have specifically mentioned.
So on the balance of what Luke records in all four incidents there seems to be a consistency that tongues (and not healings) occurred each of the four times the ‘circle of baptism’ was enlarged.