After His resurrection, Jesus appears for forty days to his followers. St. Paul tells us that Jesus appeared to more than five hundred men, revealing the glory of the resurrection. After all of these appearances Jesus gave His disciples final instructions before He ascended into heaven to intercede for all who enter into His sacrifice.
The instruction that Jesus gave the Apostles was to go and make disciples of all nations, baptizing them in the name of Father, the Son, and the Holy Spirit (Matthew 28:20). However, they do not immediately do this. Jesus had also promised them on the night before He died at the Last Supper that He would send them a helper: His Holy Spirit. This Spirit would give the Apostles and all they endowed with it, the ability to live the life of Jesus as Jesus had lived it. Without the Spirit, the Apostles did not have the strength to persevere in doing the will of the Father. So they waited.
For nine days they prayed in the upper room in Jerusalem. On the tenth day (fifty days after the resurrection of Jesus) a loud rushing wind filled the place where they were praying and tongues of fire appeared and rested on each of them. They were filled with the Holy Spirit, and immediately went out to preach Jesus as the resurrected Son of God. All the people in Jerusalem were astounded because they could hear the Apostles preaching each in their native language. This was so shocking that some people accused the Apostles of having drank too much wine.
Peter then took a position of authority and spoke to all the people as head of the eleven (Judas had killed himself after he betrayed Jesus). Peter quickly refuted the claim of drunkenness by pointing out that it was only nine in the morning. He then preached to all the people the truth of Jesus, using the scriptures to show that He was truly risen from the dead and the Messiah. When the people heard this, many believed, and asked what they should do as a response of faith. Peter’s answer is simple: repent, be baptized, and receive the Holy Spirit. Those who do so would be saved. Approximately three thousand people were baptized that day and the Church or assembly of believers was born. Those who were baptized entered into the Christian life by devoting themselves to the Apostles teachings, participating in the breaking of the bread, sharing their things in common for the good of others, and committing to a life of prayer.
The event of Pentecost set in motion the life of the early Church, and this life has continued to this day. From the beginning day of the Church we see the sacraments of initiation given to all converts to Chrisitnity. Peter exhorts them to repent and be baptized (Baptism) and receive the Holy Spirit (Confirmation). All who have been baptized share in the Breaking of the Bread (Eucharist). This is the same foundation of the Catholic Church today, even if the timeline of events varies a little.
In addition, Pentecost begins the age of the Holy Spirit. Those who receive the Holy Spirit enter into the life of Jesus. Thus, the Church is called the Body of Christ, because those who live in Jesus’ Spirit become His hands and feet on the Earth until He comes again. We see this evident with the many signs and wonders that the Apostles worked. In addition, the earlier Church’s care for the poor and love for one another was evident to those around them. So much so that love became the main characteristic of the Chrisitian.
Finally, Pentecost is the rectification of the pride of the Tower of Babel that took place thousands of years prior. Men came together to build a tower out of Pride and God confused their speech making them unable to understand one another or complete the tower. Yet at Pentecost, men and women come together in an elevated space (the upper room) for the glorification of God and the Holy Spirit descends upon them. Instead of confusing their speech, all those who spoke different languages could understand the preaching of the Apostles. Instead of coming together to glorify themselves, the Apostles and disciples were brought together for the glory of God. Thus, the Church of Christ was born, and it endures to this day. This is the community that God desired for His children and He sustained it with His Spirit.
The Church quickly spread and continued its saving work through the power of the Holy Spirit. Steadily, the number of believers increased and devoted themselves to the life of Jesus with Him as their Lord. Jerusalem was the site of Pentecost and the first converts, but God desired for the whole world to enter into His life. It wouldn’t be long before Christianity was brought to not only the Jews, but the Gentile nations as well.