The disciples watched Jesus as He was to physically leave them and was lifted into the sky. From that mountain they went out and preached everywhere. They were left with the promise that He would always be with them, and He was.
“When the Lord Jesus had finished talking with them, he was taken up into heaven and sat down in the place of honor at God’s right hand. And the disciples went everywhere and preached, and the Lord worked through them, confirming what they said by many miraculous signs.” – Mark 16:19-20