What was the purpose of everything Jesus said and did in his earthly ministry?
Everything Jesus said and did during His earthly ministry was intended to demonstrate and prove to the Jewish people of that generation that He was the promised King, the Christ, so they would recognize Him as the fulfillment of Israel's covenant promises.
Les explains that the signs Jesus performed—the blind receive sight, the lame walk, lepers are cleansed, the deaf hear, the dead are raised, and the poor have the gospel preached to them—were meant to tell John he did not have to look for another. He is the Christ, even though John was in prison. Carrying that through His earthly ministry, everything Jesus says and does is to prove to the Jew of His day that He is this promised King. Les connects this to the government promised in Isaiah 9:6-7, where the government shall be upon His shoulder.