What is an example of strength in the deities in each of these works: Gilgamesh, The Old Testament, the Iliad, and the Odyssey?
In the epic of Gilgamesh, the Old Testament, and both surviving Homeric epics, the deities demonstrate their strength in a variety of ways.
In Tablet 11 of the Gilgamesh epic, the divinity Enlil brings about the flood about which Utanapishtim tells Gilgamesh.
Similarly, in the Old Testment book of Genesis, Yahweh brings about the flood that Noah and his family survived.
In keeping with this watery theme, we shall recall that in Homer's Odyssey (Book 5), the sea divinity Poseidon rouses a storm that wrecks Odysseus' raft and causes him to wash ashore in the land of the Phaeacians.
Finally, in Homer's Iliad, the river god Scamander attacks Achilles, who is aided in his battle by the god Hephaestus, who uses fire to drive back the river:
Then Hephaestus turned his bright flame on the river itself...The mighty River himself was scalded, and cried out to the god: ‘Hephaestus, you’re a match for any immortal. I’ll not fight you while you’re wreathed in flame. Cease this battle, and let noble Achilles drive the Trojans from their city. (A.S. Kline translation)