Why is it important to see that Peter had no Gentile ministry until Israel's king was in place?
It explains why the Twelve remained in Jerusalem under severe persecution rather than fleeing to other cities or evangelizing Gentiles. They understood that a Gentile ministry could not begin until Israel's king was in place, so this recognition opens the Bible with remarkable clarity.
Les teaches that Peter and the eleven perfectly well understood they could not go out and evangelize the Gentile world until Israel's king was in place. That is why the twelve stayed in Jerusalem in spite of the horrible persecution; if they left Jerusalem, the Messiah would come again and they would be gone, so they were not about to go to Cairo, Rome, or anywhere else. Les admits this is hard to swallow and took him a long time to pass on from the Word, but once seen, the Bible opens up clear as a bell. He also points to Acts 11:19, where those scattered by the persecution about Stephen went as far as Phoenix, Cyprus, and Antioch, backing up what he said.