In the days after his resurrection Jesus had been speaking about the Kingdom of God. So the question asked by the disciples in in Acts 1 v 6 is a reasonable one. There was much about this Kingdom they wanted to understand and know about. Jesus knew the Holy Spirit would provide all they needed to be his commissioned servants, but as the eternal King he must return to the glorious heavenly Kingdom and assume His place at the right hand of the Father. This incredible day begins for all disciples the period of waiting and watching that Jesus spoke of, a day that will end when Jesus returns to judge and to reign.