Bellerophon provides a lesson in the proper relationship between a mortal hero and the gods. When he was young he honored the gods and won their favor but, then his pride got the better of him and led to his downfall.
Bellerophon was the son of Eurynome, wife of Glaucus, by Poseidon. He was raised by Glaucus who thought Bellerophon was his own son. Considering both his fathers involvement with horses it is not surprising that he quested after Pegasus. After many failures he asked the seer Polyeidus for help.
Following Polyeidus instructions he spent the night at an alter to Athena. Here he had a dream of the goddess giving him a magical golden bridle. He awoke and found the bridle from the dream in his hands. He sensibly sacrificed to both Athena and Poseidon. This done he went to where Pegasus grazed and was able to bridle and ride the horse without difficulty. Triumphant in his success he went to King Pittheus and received permission to marry his daughter Aethra. However, before the marriage could take place he accidently killed a man, possibly one of his brothers, and was banished.
He went to King Proetus to be purified for his crime. This was done but, while staying as Proetus's house guest the King's wife, Stheneboea, attempted to seduce him. As an honorable man Bellerophon rejected her advances. This infuriated Stheneboea who then falsely accused him of attempting to seduce her.
Greatly upset, Proetus wished to be rid of Bellerophon without having to accuse him publicly. He was also concerned about harming a house guest as this was an offence to the gods. So he sent Bellerophon to deliver a sealed message to his wife's father, King Iobates.
Arriving on Pegasus, Bellerophon was warmly received and settled in as Iobates house guest. Iobates unsealed and read the message thus learning of Stheneboea's accusations against Bellerophon. This left Iobates in the same predicament of acting against a guest that had troubled Proetus.
Iobates solution was to ask Bellerophon to undertake a series of heroic but, normally deadly tasks. However, Bellerophon's courage and skill as an archer combined with Pegasus as a mount allowed him to prevail. In addition his parentage, his sacrifices, and his acts of honor brought him the favor of the gods. His first task was to kill the terrible Chimaera. Succeeding here he was sent to conquer the neighboring Solymi tribe, who were Iobates traditional enemies. When he defeated them the King sent him to fight the Amazons. He was again victorious. In desperation Iobates laid an ambush against Bellerophon using his entire army. This army was killed to the last man.
At this point Iobates had the wisdom to notice that something was very wrong. He realized that the gods favored Bellerophon and that this favor would not have been given to a dishonorable house guest. Iobates succeed in making amends by giving Bellerophon half his kingdom, including the best farm land and his daughter Philonoe in marriage.
There are two stories concerning the fate of Stheneboea. One that Bellerophon extracted revenge by taking her for a ride on Pegasus then shoving her off to fall to her death. This seems unheroic. In the other version Stheneboea hears that Bellerophon has married her sister. She knows that this means her slander will be reveled and chose to kill herself.
It appeared that Bellerophon would live happily ever after. His glorious deeds were widely sung. He was happily married. Philonoe bore him two sons, Isander and Hippolochus, and two daughters, Laodameia and Deidameia. As a king his subjects loved and honored him.
All this was not enough for Bellerophon. In his arrogance he decided that he could ride Pegasus to Mount Olympus and visit the gods. Zeus quickly put an end to his trip by sending the gadfly to sting Pegasus and throw Bellerophon. He survived his fall but, was crippled. He spent the rest of his life wandering the earth. No man would help him because of his offense to the gods. He died alone with no one to record his fate.