Jesus went through all the towns and villages, teaching in their synagogues, preaching the good news of the kingdom and healing every disease and sickness. (Matthew 9: 35)

Jesus was leading (periago), teaching (didasko), healing (therapeuo), and kerusso (proclaiming, serving as a royal herald, announcing something that has already been done) the euaggelion (glad tiding, good news, reward, joy) of the kingdom.

Kerusso euaggelion is a kind of redundancy, presumably to give emphasis. Emphasizing what?

Jesus is formally and officially announcing (kerusso) the reward for having announced glad tidings (euagellion). In the ancient world the royal messenger who brought news of a great victory, or the birth of an heir, or the marriage of a princess, or some other good news would be rewarded.

For example in Homer's Odyssey, the hero has already returned home but has not yet declared his identity. In a conversation with a swineherd who is sure Odysseus is dead, the King-in-disguise offers, “Friend, since you do utterly deny, and declare that he will never come again, and your heart is ever unbelieving, therefore will I tell you, not at random but with an oath, that Odysseus shall return. And let me have a reward for bearing good tidings, as soon as he shall come, and reach his home; clothe me in a cloak and tunic, goodly raiment."

The reward for bearing good tidings is the euagellion of Matthew.

Jesus is no longer in disguise. He is publicly proclaiming the good news of something that has already happened: the kingdom of heaven is at hand. Jesus is also claiming the reward for bringing this good news.

What is the reward?