Betrayal is a word from Middle English and it was originally bitrayen. There are many forms of betrayal, and it is common within a culture to have varying degrees of punishment for betrayal, most of which are rather severe as it is considered one of the more painful and unsympathetic acts a person may do.
Why betrayal is considered so severe?
Almost all betrayal involves some sort of premeditation, including if the betrayal is through an act of omittance. It involves using the trust that has been built up and earned for personal use or gain. The trust is often broken once the betrayal is clearly visible.
The severity of betrayal
It is considered a severe act because it is more than just lying. People may lie to gain trust in order to betray it, but the fact is that lying on its own merit is not as bad as betrayal. A person may lie to another without any form of trust existing, and the more trust that has built then the bigger the betrayal. There is often an amount of lying involved in a betrayal, though this is not always the case.
More unsympathetic than most crimes
A person may murder out of revenge or in order to help ease suffering, but since betrayal requires trust and the breaking of that trust, it is considered more unsympathetic. A person may understand a theft in order to feed a family, but people rarely understand a premeditated act of building trust in order to break that trust for personal gain.
If trust has been established, then even aiding the enemy of the one that trusts is still betrayal. It is also betrayal if one uses the trust of one person (or thing) in order to gain the trust of another person (or thing); the thing may be a company or even a country. The longer the trust is maintained after the betrayal, then the more severe the act of betrayal is.
After six years of marriage a woman may sleep with another man. This is a betrayal because there was a promise of monogamy, plus the implied emotions and feelings that are tied with the woman claiming she is in love are all part of promises based on trust. The woman says she has certain feelings of love to the point where she marries in a large symbolic gesture implying she intends to spend her live with just one man–both emotionally, physically and sexually. These are all the trust building elements, and the actual affair is the point of betrayal. Whether the man finds out or not, he has still been betrayed. The betrayal grows ever worse the longer the woman denies telling the man about her infidelity.
Betrayal is the act of building trust and then using that trust for personal gain. It often involves breaking the trust and often involves lying. Betrayal is anything that acts out of the interest of a something or someone when that something or someone has been lead to believe that would not happen.