The Iliad 11.173–185

her neck he seizeth first in his strong teeth and breaketh it and thereafter devoureth the blood and all the inward parts: even in like manner did lord Agamemnon, son of Atreus, follow hard upon the Trojans, ever slaying the hindmost, and they were driven in rout. And many fell from their chariots upon their faces or upon their backs beneath the hands of Atreus' son, for around and before him he raged with his spear. But when he was now about to come beneath the city and the steep wall, then, verily, the father of men and gods came down from heaven, and sate him down on the peaks of many-fountained Ida; and in his hands he held the thunder-bolt. And he sent forth golden-winged Iris to bear his message: Up go, swift Iris, and declare this word unto Hector: So long as he shall see Agamemnon, shepherd of the host, raging amid the fore-most fighters, laying waste the ranks of men, so long let him hold back, and bid the rest of the hostfight with the foe in the fierce conflict. But when, either wounded by a spear-thrust or smitten by an arrow, Agamemnon shall leap upon his chariot, then will I vouchsafe strength to Hector to slay and slay until he come to the well-benched ships, and the sun sets and sacred darkness cometh on.