Why was the prophetic program interrupted instead of continuing straight to the tribulation and kingdom?
The prophetic program was interrupted because Israel rejected the message and the offer of the kingdom. Peter preached that Joel's prophecy was being fulfilled and expected the tribulation and kingdom to follow, but Israel's rejection meant God did not proceed straight to those events. Instead, a church age that Peter did not foresee was introduced.
Les explains that Peter did not have Christ's omnipotent insight and could not stop at the right place. Peter preached as if the whole prophetic program was coming, with no idea of a church age. In Acts 2, he said the Pentecost events were what Joel spoke of, and he could see the next steps: the tribulation, then the return of Israel's king and the kingdom. After that, Israel could bring Gentiles to a knowledge of God. But Israel rejected it. Jesus knew in Luke 4 where to stop, and that last half of the verse would not be completed until much later. Peter, however, went right on through it and did not know the difference. So the program was interrupted because Israel rejected the offer, and a church age not revealed to Peter began.