What did Jesus do during His three years of earthly ministry?
During His three years of earthly ministry, Jesus presented Himself to the nation of Israel as the fulfillment of all the prophecies. He came to Israel, and after that ministry they crucified Him. His ministry was primarily, not exclusively, to the Jew.
Les teaches that the three years of earthly ministry are placed after Israel's rejection of the prophetic program and before the book of Acts. For those three years, as we study the Gospels, Jesus presented Himself as the fulfillment of all the prophecies as He came to the nation of Israel. Then they crucified Him, and Peter picked up the torch and continued that same program in Acts. Les explains this program was primarily, not exclusively, Jew only, with exceptions. Israel continued to reject, and then came a body of truth never before mentioned, which Paul calls the mysteries.