The resurrection of Jesus was a miracle. This just didn’t happen. The religious leaders bribed the guards to say his body was stolen instead of saying he rose from the dead and left the tomb. But Jesus didn’t just want it to be a ‘he said’ versus ‘he said.’ In Acts it says He presented himself to the disciples showing his wounds that verified He was who He said He was. He revealed himself to over 500 people in a 40 day period. He told them to stay in Jerusalem until ‘the promise of the Father baptized them with the Holy Spirit.’
He taught them about the kingdom of God and gave them the Great Commission to go out through Judea and Samaria and then to the ends of the earth and be witnesses and tell the gospel to everyone they met. And while he was talking to them he was lifted up and a cloud took him from their sight. They were looking up wondering what had just happened and two angels appear and say “Why are you standing there looking up at the sky? This same Jesus who was taken up to heaven will one day return the same way.”
It would have been an easy transition after you just saw Jesus leave and the angels say he is going to come back the same way to go out to the hill and just sit down and watch the sky and wait. But that wasn’t what they or we are supposed to do. The Great Commission is our assignment. We are to tell the gospel to everyone. We know that one day He will come back, but we are to be witnesses for Him until that day happens.