'Reward' in the Bible

when the person told me, ‘Look, Saul is dead,’ he thought he was a bearer of good news, but I seized him and put him to death at Ziklag. That was my reward to him for his news!

However, Ahimaaz son of Zadok persisted and said to Joab, “No matter what, please let me also run behind the Cushite!”Joab replied, “My son, why do you want to run since you won’t get a reward?”

Since your servant is only going with the king a little way across the Jordan, why should the king repay me with such a reward?