The outpouring of the holy spirit is for an assignment. The mandate Jesus gave to the disciples was an order/ authority to fulfill the assignment. Acts 1:1-11.
What is the Kingdom mandate given to the disciples? First, Jesus first began to do (verse 1) before he started to teach. So when he began to preach He was preaching what He is (not what is has not experienced). The sermon observes the mandate Jesus began and left to us to complete.