Epics of Homer
The epics of Homer, the Odyssey and the Iliad, are two of the most famous Greek works. Both of these show extremely high influence from religion, and influence from politics as well.
The Odyssey is the tale of Odysseus the king. Odysseus, after conquering Troy in the Trojan War, thinks too highly of himself and rebels against Poseidon. Not only is Poseidon angered because of his rebellious nature in general, but without the serpent Poseidon sent, Troy would not have been conquered. Because of Poseidon's anger, Odysseus doesn't get home to Ithica for many, many years. Along his way, he meets many of the gods, such as Hermes and Athena.
The Iliad is focused mainly on the stories of individuals, but many scenes with the gods as present as well. In the first day of battle, there is a council of the gods to decide their course of action. Later on, there is a scene where Zeus is frustrated with Athena and Hera, because they have not been able to destroy Troy.
The gods choose their course of action, and inspire the armies to break their oaths of peace and battle again. Athena does this by inspiring an archer to fire at the enemy's leader.
Later on, in the longest book of the Iliad, there is the account of Diomedes, a man who's rage in battle caused him to defeat two gods - Aphrodite and Apollo. It is accounted that the source of his strength was from Athena, the Goddess of War.
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