God's leaders in the Old Testament spoke through the power of the Holy Spirit. Jesus was God in human flesh, so Luke emphasized that Jesus' words carried the authority of God — giving "instructions through the Holy Spirit." We will see some of these "instructions" on the next three days. When Jesus spoke these words to his "chosen apostles," they were some of his last words with them on earth. As we read these things that the Lord said, we will see that they detail the importance of the challenges that lay ahead for the apostles. Jesus told the apostles to wait in Jerusalem. They had witnessed great things. They had been chosen to experience the unimaginable. Nevertheless, to do what they needed to do, they needed the power and authority of the Holy Spirit. So, Jesus promised to pour out the Holy Spirit on them, as happened during the Pentecost Festival. The Spirit would empower and inspire those once fearful and deeply flawed disciples, making them bold as they shared their message with the authority of Jesus. Their courage empowered by the Holy Spirit would change the course of history, forever.