The biblical narrative of Pentecost is given in the second chapter of the Book of Acts. As recounted in Acts 2:1-6:[4]

And when the day of Pentecost was fully come, they were all with one accord in one place. And suddenly there came a sound from heaven as of a rushing mighty wind, and it filled all the house where they were sitting. And there appeared unto them cloven tongues like as of fire, and it sat upon each of them. And they were all filled with the Holy Ghost, and began to speak with other tongues, as the Spirit gave them utterance. And there were dwelling at Jerusalem Jews, devout men, out of every nation under heaven. Now when this was noised abroad, the multitude came together, and were confounded, because that every man heard them speak in his own language.

While those on whom the Spirit had descended were speaking in tongues, the disciple Peter stood up with the eleven and proclaimed to the crowd that this event was the fulfillment of the prophecy ("I will pour out my spirit") in Joel 2:28-29. Acts 2:41 reports: "Then they that gladly received his word were baptized: and the same day there were added unto them about three thousand souls."