Jesus Christ is our supreme example of humility. His entire life is a demonstration of His humility. He left His throne in heaven and decided to dwell with mere humans. He chose to go through the toil and sufferings that human beings go through. Even though He was the Creator, He was maltreated and dehumanised by His creation. Nevertheless, He endured all such suffering for our sake. In all these, Jesus had the ultimate goal of saving humanity and therefore He chose to endure for our sake.
In the same vein, as an ambassador, you must display this same attitude of Christ. Humility is the absence of pride and arrogance. It is an essential virtue but very difficult to uphold. The result or reward for being humble is elevation by God. When elevation comes and you are not careful, pride may set in and this can also result in your downfall. God wants to elevate you but for this to happen, you need to be humble.