The union of man and wife has been a sacred union throughout history. Through rituals such as oaths and vows humans have promised to abide by the laws society has created and altered through time. Because of this long and evolving history, the guidelines have evolved as well, but general ideals have always been abided by. Medea's marital relationship with Jason proves that while this union is said to be sacred, is very much up to one's own interpretation of what falls under this definition.
Even in the beginning, Jason's and Medea's relationship is unstable. One can learn through other legends that Medea willingly gives up her family and homeland for her love of Jason. While it may be assumed that this would create a stronger bond between the two, the lack of communication leaves Medea and Jason with different perspectives of the situation of their relationship. .
These early events in Medea's and Jason's relationship clearly forshadow the situation that unfolds in Euripides" play. Jason's actions in marrying Creon's daughter are noble enough if his reasoning is indeed true, but unravel in a Greek tragedy filled with passionate revenge. He does not consider his marriage to Creon's daughter a sinful strike at his relationship with Medea, and yet Medea feels it is a crime unlike any other and must be treated as such. .
It is clear that Medea believes that her bond to Jason is not only lawful but emotional, and while Jason too feels that he has a loyalty to Medea, he does not see their relationship as such an emotional one. His willingness to marry another woman is evidence that his emotional attachment to Medea and their relationship is not like hers. It can be reasoned that this is because Jason has not sacrificed as much for the sake of their relationship, but when it comes down to the facts, he took the same vows Medea did. This disagreement in interpretation is the beginning of the end for Jason's and Medea's relationship from the start.