Acts 2:1-4, 38-39

When the day of Pentecost had come, they were all together in one place, and suddenly a sound came from heaven like a rushing violent wind, and it filled the whole house where they were sitting. There appeared to them tongues resembling fire, which were being distributed [among them], and they rested on each one of them [as each person received the Holy Spirit]. And they were all filled [that is, diffused throughout their being] with the Holy Spirit and began to speak in other tongues (different languages), as the Spirit was giving them the ability to speak out [clearly and appropriately].

And Peter said to them, “Repent [change your old way of thinking, turn from your sinful ways, accept and follow Jesus as the Messiah] and be baptized, each of you, in the name of Jesus Christ for the forgiveness of your sins; and you will receive the gift of the Holy Spirit. For the promise [of the Holy Spirit] is for you and your children and for all who are far away [including the Gentiles], as many as the Lord our God calls to Himself.” [Is 57:19; Joel 2:32]