The entire Universe functions on one single entity which is Dharma. All life is bound to it especially mankind. While emotions of friendship, love, trust, jealousy, hatred and many more rule the human mind, the ultimate truth is that Dharma is above everything and everyone else. Governed by these emotions, man always lets his emotions rule him, but each and every time Dharma comes around giving a strong message that those who miss following Dharma pay a very high price for their actions, just as it did happen with Karn, who in spite of being a virtuous person, went for downfall due to his friendship with Duryodhan.
Not everything was wrong when Karn first met with Duryodhan. When Karn was ridiculed in the court of Hastinapur for his low birth, Duryodhan questions the inequalities of the society and recognises Karn’s talent as a warrior rather than his status in the society. With this incident, Karn pledges his loyalty to Duryodhan forever. But this loyalty costs his dearly, as Duryodhan stands on the side of injustice, and Karn although being a noble man, bound by friendship, had to stand against Dharma.
Karn was a virtuous person known for his honesty, benevolence and courage, but all his virtues were overshadowed in the company of Duryodhan. Karn had to become a silent man watching all the mistakes committed by Duryodhan and Shakuni, due to his friendship with Duryodhan. As a friend, it was the foremost duty of Karn to advise Duryodhan from doing evil deeds, but Karn ignores it and supports Duryodhan as he only sees the angle of friendship between them, but fails to understand that adherence to Dharma was above everything else.
Before the war of Kurukhsetr, when Shri Krishna reveals to Karn his original identity of being the son of Kunti, Karn is shocked, but does not change sides. Although Shri Krishna advises him that Dharma was greater than anything and one should never take sides on the stand of Dharma, Karn disagrees and supports Duryodhan although he knew that he was on the losing side. Bound by his word, Karn finally makes the ultimate sacrifice of giving his life for Duryodhan in the battle, as a cost of their friendship.
Karn’s life is definitely an example for loyalty and friendship so pure that he did not think twice to forgo his life for the sake of his friend. But, he had to face a different destiny. Because of his wrong choice of friendship, Karn is remembered as a person who was torn between truth and injustice, and with a friendship costing Dharma, the price Karn had to pay was a lesson that friendship is to be done with a pure heart and sacrifice, but it should never go against Dharma.