The two powerful sons of Cronus, Zeus and Poseidon,
their deathless spirits warring against each other,
were building mortal pains for seasoned heroes.
Zeus willing a Trojan victory, Hector’s victory,
…But Poseidon surging in secret out of the gray surf
went driving into the Argive ranks and lashed them on,
agonized for the fighters beaten down by Trojans,
and his churning outrage rose against great Zeus,
…Both gods knotted the rope of strife and leveling war,
strangling both sides at once by stretching the mighty cable,
never broken, never slipped, that snapped the knees of thousands.

– Homer

The Iliad, Book 13, lines 400-403, 408-411, 417-419. The passage is about the great clash of wills between the gods Zeus and Poseidon during the war. Zeus is willing a Trojan victory to give Achilles more glory. But Poseidon is on the side of the Achaeans. Homer uses metaphors here to describe the gods controlling the movements of the battle through invisible cords tied to the armies, which they pull at alternatively as in a tug of war. The metaphors: "the rope of strife and leveling war" and "strangling both sides at once by stretching the mighty cable."