but you will receive (a)power when the Holy Spirit has come upon you; and you shall be My (b)witnesses both in Jerusalem, and in all Judea and Samaria, and even to the remotest part of the earth."
v.8- (b) This is the main reason for this endowment of the power of the Spirit; to be His witness to the world.
Jesus gives specific instructions to the progression of the dispersing of the gospel; first to Jerusalem, then Judea, then Samaria, then the rest of the world. Again this goes back to God’s plan. It was always the Jew first and then the Gentile. Jesus followed these same orders, going to Jerusalem, Judea, then Samaria and then the Gentiles, and now He is relaying these same marching orders for His disciples.
The way it plays out is fascinating because the disciples didn’t take these orders and make a plan to spread the gospel in this fashion. It was the hand of God that directed them thru the chaos of life and thru this, fulfilled His plan.
After Jesus ascended, they waited in Jerusalem, as Jesus instructed. They really did not know what they were waiting for. They knew Jesus promised they would receive the promise of the Father and be baptized in the Holy Spirit, but I don’t think they really knew what all that meant; but they were faithful and patient and on the day of Pentecost they were filled with the Holy Spirit, just as Jesus had promised.
This day, the Feast of Shavout (weeks), was established thousands of years prior, as the exact point in time the Holy Spirit would be given to the Church.
Leviticus 23:15 tells us from the day after the Sabbath, count 50 days to the day after the seventh Sabbath, this is the Day of Pentecost; basically 50 days from first weekly Sabbath after the Passover or 49 days from the Feast or Firstfruits.
The Day of Pentecost is always 49 days from the Feast of Firstfruits. In the year 32AD, the Holy Spirit came down on Sunday, June 5th.
After the apostles received the Spirit they immediately start to preach the gospel in Jerusalem with boldness. In a matter of days, thousands of Jews receive Jesus. Persecution from the Pharisees arises. Peter and John are thrown in prison, but the hand of God releases them, finally Stephen is stoned to death and this forces the disciples to disperse and travel to other places in the world. It is this persecution that leads to the spread of the gospel in the exact order that Jesus commanded. This is what I think is so amazing. Even thru all the chaos, because of this persecution, it actually enables the disciples to reach out to other parts of the world, Acts 8:4, 11:19-21, to the Jew first in Jerusalem and Judea, then Samaria, then the Gentiles in the rest of the world.