The Kingdom of Heaven is the divine institute which will administer the Blessing of the Promise to Abraham.
The Gospel, of Good News, is God's plan for reconciling fallen man to himself, that he might have a people to bear His Name forever. God revealed His plan through His servant - the prophets. The revealed Word of prophecy foretells events directed by God, to culminate in the fulfillment of His eternal plan, the Kingdom of God - when Jesus Christ shall be "King over all the Earth"