PENTECOST
Extracted from Wikipedia - https://en.wikipedia.org/wiki/Pentecost
The biblical narrative of Pentecost is given in the second chapter of the Book of Acts. Present were about one hundred and twenty followers of Christ, including the Twelve Apostles (i.e. the Eleven faithful disciples and Matthias who was Judas' replacement), his mother Mary, various other women disciples and his brothers
Their reception of the Holy Spirit in the Upper Room is recounted in Acts 2:1–6:
….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 Spirit, and began to speak with other languages, as the Spirit gave them utterance. And there were dwelling at Jerusalem, 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 many languages, the Apostle Peter stood up with the eleven and proclaimed to the crowd that this event was the fulfilment of the prophecy ("I will pour out my spirit”). In Acts 2:17, it reads: 'And in the last days,' God says, 'I will pour out my spirit upon every sort of flesh, and your sons and your daughters will prophesy and your young men will see visions and your old men will dream dreams." He also mentions that it was the third hour of the day (about 9:00 AM), then reports: "Then they that gladly received his word were baptised: and the same day there were added unto them about three thousand souls."
Peter stated that this event was the beginning of a continual outpouring that would be available to all believers from that point on.