Herald
Herald: in ancient Greece the man who made announcements on behalf of a king or the city's government.
The herald was the person - almost always a man - made announcements on behalf of a king or the city's government. Heralds could also be sent out as messengers. They were represented with a herald's staff, the kerukeion (κηρύκειον) or caduceus.
In Sparta, the office of herald was inherited within the family of the Talthybiads, who claimed to be descendants of Talthybius, the herald of the legendary king Agamemnon.note Herodotus of Halicarnassus remarks that this custom also existed in Egypt.note
If the portrayal of Talthybius in the plays of Euripides is representative of the herald's activities, he had considerable independence in the way he carried out his orders. Killing a herald was considered a serious crime; the murderers were believed to be cursed and ought to be expelled. If this did not happen, it might be a cause for war. For example, the assassination of a herald by the Megarians was one of the complaints leading to the outbreak of the Archidamian War (431 BCE).
The angels of the Judaeo-Christian-Islamic tradition are based on the ancient heralds.