The disciples were instructed not to depart from Jerusalem because Jesus had promised them that they would receive the Holy Spirit not many days from then. This promise was fulfilled on the day of Pentecost when the Holy Spirit came upon them with power and they were filled with boldness to proclaim the message of the gospel to the world. From Jerusalem, the disciples were positioned at the heart of the religious and political center of the Jewish people, providing an ideal location and platform for them to begin spreading the message of salvation to others.
