3.2 Acts -- Pentecost
The era of the New Covenant was inaugurated by the Resurrection of Jesus, and instituted on the Day of Pentecost. This Jewish festival occurs 50 days following Passover, and was called the Feast of Weeks or Harvest in the Jewish calendar. It was a time of thanksgiving for the firstfruits of the harvest.
When the day of Pentecost came, they were all together in one place. Suddenly a sound like the blowing of a violent wind came from heaven and filled the whole house where they were sitting. They saw what seemed to be tongues of fire that separated and came to rest on each of them. All of them were filled with the Holy Spirit and began to speak in other tongues as the Spirit enabled them (Acts 2:1-4).
There were approximately 120 people in the room (Acts 1:15), and all were Jews who were believers in the teachings of Jesus. Many were witnesses of his post-Resurrection appearances.
a. The coming of the Spirit upon them harks back to the anointing of kings and prophets in the Old Testament:
Then the Lord came down in the cloud and spoke with him, and he took of the Spirit that was on him and put the Spirit on the seventy elders. When the Spirit rested on them, they prophesied, but they did not do so again. However, two men, whose names were Eldad and Medad, had remained in the camp. They were listed among the elders, but did not go out to the Tent. Yet the Spirit also rested on them, and they prophesied in the camp. A young man ran and told Moses, "Eldad and Medad are prophesying in the camp." Joshua son of Nun, who had been Moses’ aide since youth, spoke up and said, "Moses, my lord, stop them!" But Moses replied, "Are you jealous for my sake? I wish that all the Lord's people were prophets and that the Lord would put his Spirit on them!" (Num 11:25-29)
As Saul turned to leave Samuel, God changed Saul’s heart, and all these signs were fulfilled that day. When they arrived at Gibeah, a procession of prophets met him; the Spirit of God came upon him in power, and he joined in their prophesying (1 Sam 10:9-10).
So Samuel took the horn of oil and anointed him in the presence of his brothers, and from that day on the Spirit of the Lord came upon David in power (1 Sam 16:13).
This anointing also was a fulfilment of Jesus' earlier promise, and caused a change in the lives of his followers:
"The wind blows wherever it pleases. You hear its sound, but you cannot tell where it comes from or where it is going. So it is with everyone born of the Spirit" (Jn 3:8).
"And I will ask the Father, and he will give you another Counselor to be with you forever -- the Spirit of truth. The world cannot accept him, because it neither sees him nor knows him. But you know him, for he lives with you and will be in you" (Jn 14:16-17).