Old King Aeson of Thessaly was dying. His baby son Jason was too young to rule in his place. The king asked his brother Pelias to rule for him until Jason might become a man. Pelias agreed but secretly decided that Jason would not ever become king.  Pelias begged the advice of an oracle. In those days the oracle was believed to be able to predict the future. The oracle burned some magic powder and spoke some magic words.  Then the oracle said to Pelias, "Fear not anyone who cometh neither wearing nor not wearing a shoe." Pelias believed this strange reply. In order that he might be safe he banished Jason to a faraway land.  There Jason was sent to study with a centaur named Chiron,

half man and half horse.  Jason did not know that he was born of royal origin.
The centaur, however, told him about his father, the king.  Jason and the centaur consulted an oracle so that Jason might recover the rule and his kingdom.  The strange reply of the oracle was: "Who will seek the kingdom shall wear a leopard's hide."  Jason killed a leopard, put on its skin, and said goodbye to the centaur. 

While he was journeying to Thessaly he came to a deep river. People on the bank warned him not to cross.  Jason stepped into the raging river. The people watching groaned as he was thrown down.  Jason, however, grasping a branch, pulled himself to safety on the far bank.  Although he had lost one sandal in the river, nevertheless he went on with one foot bare. The people of Thessaly, when they saw him wearing only one shoe, recalled the old prophecy.  Pelias, seeing Jason, put on an appearance of joy and drank to his health.  Then he told Jason about a Golden Fleece in Colchis which was guarded by dragon who never slept.   Pelias was happy because Jason said that he would capture the Golden Fleece. He was sure that Jason would perish.                 

Jason ordered Argus, a famous ship architect, to build a ship large enough for fifty men.  Jason called the ship the "Argo" and set sail with 50 brave men who were called the Argonauts. They had to pass between two cliffs which clashed together when anything passed between them. Reaching the cliffs, Jason released a dove. The dove flew between the cliffs, which clashed together with a terrific noise. The Argonauts reached Colchis. Jason told the king that he had come to take the fleece.  

The king laughed. Then he ordered Jason to yoke bulls which breathed out flames from their mouth. 

Jason saw in a nearby field the bulls which were pawing the ground and scorching it with their fiery breath.  Jason was in despair. Suddenly Medea, the king's daughter, who was in love with him, appeared.  She told Jason that she would help him to get the fleece if he promised to marry her.  When he gave his word, Medea gave him a magic herb and a heavy black stone. The next day at dawn Jason went to the field. He held out the magic herb to the bulls rushing toward him.  Jason yoked the bulls that had become tame to a plow.  The king arrived and was surprised to see Jason plowing the field.  

 He gave Jason a helmet filled with dragon teeth. He ordered him to plant them in the field.  When the teeth were planted, Jason, terrified, saw that an army was rising from the ground.  While they brandished their spears and rushed toward him, Jason threw the stone given by Medea.  The stone struck a soldier. He, believing that his neighbor had done this, turned angrily and struck the soldier.  A general fight followed in which every soldier was killed. 

Then Medea came to Jason and gave him a magic liquid.  Jason went to the garden where he saw the fleece on a tree guarded by a fierce dragon.  Jason threw the magic liquid into the dragon's face and it immediately fell asleep. Then Jason cut off the dragon's head and seized the golden fleece.  Jason, the Argonauts, and Medea ran to the ship and set sail. The king and his soldiers pursued Jason but could not overtake him.  Jason reached Thessaly and compelled Pelias to yield the rule to him.