Tongues in Acts
The first clear example is at Pentecost, after Jesus’ followers were filled with the Holy Spirit. They began to speak in other tongues, and visitors from many nations heard God’s works being declared in their own languages (Acts 2:4, Acts 2:11). This means that, in this event, the tongues were real human languages which the speakers had not learned in the ordinary way.
Tongues also appears when the Holy Spirit is poured out on new groups of believers. When Peter visited Cornelius’ household, the Jewish believers heard the Gentiles speaking in tongues and praising God (Acts 10:46). In Ephesus, people who received the Holy Spirit spoke in tongues and prophesied (Acts 19:6). These moments show God welcoming people from different backgrounds into his people.
And they were all filled with the Holy Ghost, and began to speak with other tongues, as the Spirit gave them utterance.
A gift, not a test of faith
Paul includes tongues and the interpretation of tongues among the gifts given by the Holy Spirit (1 Corinthians 12:10). The same chapter names other gifts too, including wisdom, knowledge, faith, healing and prophecy (1 Corinthians 12:8, 1 Corinthians 12:9). The Spirit gives these gifts according to his own will, rather than giving every gift to every person (1 Corinthians 12:11).
So speaking in tongues is not presented as a requirement for being loved by God or belonging to Christ. Paul asks whether all believers speak in tongues, expecting the answer to be no (1 Corinthians 12:30). Different gifts are meant to serve the same body of believers.
To another the working of miracles; to another prophecy; to another discerning of spirits; to another divers kinds of tongues; to another the interpretation of tongues:
Tongues in church worship
Paul does not dismiss tongues, but he is deeply concerned that gathered worship should strengthen the whole church. If someone speaks in a tongue publicly, there should be an interpreter so that others can understand and be built up (1 Corinthians 14:27). If there is no interpreter, Paul directs the speaker not to address the gathering in that way (1 Corinthians 14:28).
Understandable words are especially valuable when Christians meet together. Paul says he would prefer a small number of intelligible words that teach others over many words in a tongue (1 Corinthians 14:19). The purpose of spiritual gifts is not personal display, but love and the good of others (1 Corinthians 13:1).
If any man speak in an unknown tongue, let it be by two, or at the most by three, and that by course; and let one interpret.
Why Christians differ
Most Christians recognise that Acts 2 describes known languages. They differ over passages such as 1 Corinthians 14:2, where Paul describes a person speaking to God in a tongue that others do not understand. Some see this as evidence that tongues can include private prayer in a language unknown to the speaker. Others understand it as an unrecognised human language, particularly when no interpreter is present.
Christians also differ over whether all New Testament gifts continue in the same way today. Whatever view is held, Paul’s guidance is clear: seek gifts that help others, practise worship with peace and order, and let love guide every gift (1 Corinthians 14:1, 1 Corinthians 14:33). Reading Acts 2 and 1 Corinthians 12 to 14 closely can help you explore the question with openness and discernment.