Why couldn't Jesus minister to the Gentiles during His earthly ministry?
Christ's earthly ministry was confined to Israel because He came to the nation of Israel in the earthly promises of the Abrahamic covenant and its later covenants. He commanded the Twelve not to go to Gentiles or Samaritans, but to the lost sheep of the house of Israel. Only two exceptions occurred.
Les explains that Jesus could not minister to the Gentiles during His earthly ministry because He came to the nation of Israel in the earthly promises of the covenant made with Abraham. Under that Abrahamic covenant were later covenants: the Davidic, Mosaic, and Palestinian covenants, referring to the land of Palestine. In Matthew 10, after calling the Twelve, Jesus commanded them not to go into the way of the Gentiles or into any city of the Samaritans, who are half-breeds, but rather to go to the lost sheep of the house of Israel, God's earthly people. Thus Christ's earthly ministry was confined to His earthly people, Israel, with only two exceptions. One exception is in Matthew 15, where Jesus departed into the borders of Tyre and Sidon, on the Mediterranean sea coast, in the area now known as Lebanon.