Misinterpretations often portray the tongues as ecstatic, unintelligible gibberish or a mandatory personal prayer language for all believers today, rather than miraculous xenoglossia (known foreign languages) serving as a sign to the diverse Jerusalem crowd; others wrongly demand this exact experience as essential evidence of Spirit baptism, overlooking its unique fulfillment of prophecy in the apostolic era and the Spirit's varied gifts described elsewhere.
Acts 2:4
King James Version (1769)
4 And they were all filled with the Holy Ghost, and began to speak with other tongues, as the Spirit gave them utterance.
This passage captures the pivotal moment at Pentecost when the Holy Spirit descended upon the apostles as promised by Jesus, filling them all and enabling them to speak in other tongues—actual foreign languages they had not learned—as the Spirit gave utterance, fulfilling Joel's prophecy and inaugurating the church age with supernatural power for bold witness to all nations.