Previous Birth

In the previous birth KARNA was known as SHAHASHTRAKAWACH, HAVING 1000 TIMES MORE PROTECTIVE DEVICE ( kawach ) than any one. Lord Surya Dev gave the Boon Of 1000 Armours which has defensive power of 1000 times than any one in this universe.

To get rid from this demon, Vishnuji had agreed to help them and descended on earth in the form of two men, named Nara and Narayana. ( at present these are two mountains near Badrinath ).When this SHAHASHTRAKAWACH, was challenged by these two men, there was a long lasted war between them one by one. Thus alternating with each other,Realizing this that he had only one kawach left, So, he went and hid himself behind the Sun-god.To destroy one shield, twelve years penance was required. Nara and Narayana fought with Sahasrakavaca taking turns alternately of fight and penance. In this manner ninehundred and ninetynine shields were destroyed and one shield remained. Nara and Narayana continued fighting with the asura, till he was left with only one kavacha upon his body.Then Pralaya occurred. The daitya took shelter in the sun. With Sahasrakavacha having left the field, Nara and Narayana returned to heaven.

After a long time, with the slok uttered by Kunti as per blessing of Durvasha,a son was born to Kunti with the blessings of the Sun-god. The child was named Karna and he was born wearing a single kavacha upon himself. This evidently proved to the shocked people around him that Karna was none other than Sahasrakavacha who had taken rebirth as Karna. He is now born as Karna with one shield (kavaca). Now it is Arjuna's turn to spend twelve years in forest as penance. Both Krishna and Arjuna together are destined to kill the daitya(Karna).So as per vardan of Brahma Sahasrakavacha lived so long as he wore the kavachas,as last kawach was donated to Indra.

Detailed Version
https://freeglobaluniversity.blogspot.com/search/label/Nar

YouTube

http://www.youtube.com/results?search_query=karna

Song in praise of Karna - by Krishna / Audio

Ullathil nalla ullam
Urangaadhenbadhu
Vallavan vaguthadhadaa, Karna
Varuvadhai edhirkolladaa.

The most beautiful amongst souls
Shall never fall to the fatal tell of time
Thus, say the greatest of men, Karna
Prepare for the fate that shall be thine.

Thaaikku nee magan illai
Thambikku annan illai
Oor pazhi etraayadaa
Naanum un pazhi kondenadaa

You aren't a son unto your own mother (referring to Kunti's desertion)
And not a brother to each of your sibling (the Pandavas)
Oh! How you bore the insinuations!
I too shall be your sinner by my cunning. (The ploys Krishna uses to bare Karna)

Mannavar paNi erkum
KaNNan paNi seyya
Unnadi paNivaanadaa
Manniththu arulvaayadaa, Karnaa

He who is served by the greatest kings
(That) Krishna, to serve you, is ready
By bowing to your magnanimity.
Karna, will you grace me with mercy?

Senjotru kadantheerka
Seraatha idam sairndhu
Vanjaththil viyinthayadaa, Karna
Vanjakan, Kannanadaa

To repay the hand that fed you
You pledged your loyalty to the vile Kauravaa
And fell in the trap of great deception, Karna.
(Though) the greatest knave is the son of Vasudeva.

Neither Krishna nor Karna were working towards setting an example for posterity. Krishna the lord was aware of how the world was supposed to go and did just that. Karna the human was aware of what he was supposed to do and he did just that. Now who is to measure the greatness of each of them?

https://www.google.com/search?q=Song+in+praise+of+Karna

Clipping of Karna Play

https://www.google.com/search?q=Clipping+of+Karna+Play

Story

http://www.indiavilas.com/indiainfo/greatindian.asp?g=Karna&t=gper

Karna Greatest Quality - Greatest daanveer

A man who would never refuse the request for any gift or donation, howsoever costly that might be and irrespective of the consequences of giving to his own well being or security.

KARNA - JOINS THE WAR

http://www.urday.com/mkarnajoins.html

Karna Fault - Keeping Bad Company

Result of Bad Company

Instrumental in the vastraharan of Draupadi. When Draupadi questioned the court how she could be used as a 'bet' when Yudhishtra himself had already lost. Karna in his explanation said that since Yudhishtra himself had lost, it was immaterial what happened later, every of his belongings, now was lost to Dhuryodhana. He further added insult with these commands, "O Duhsasana, seize the garments of the Pandavas and the robes of Draupadi and hand them over to Sakuni".

Karna abets in the killing of Abhimanyu, the son of Arjuna. Six warriors including Karna disarm Abhimanyu and proceed to injure him severely with arrows. Abhimanyu’s death is ghastly and even in this instance, Karna acts on the command of Duryodhan. He could have advised Duryodhan against killing Abhimanyu in such a cruel manner against Dharma. This act tarnishes Karna’s image further because six fighting against one is against the laws of Dharma.

Even upon learning that his brothers were the ones that were being discriminated, he did not try to reason with his friend, Dhuryodhana.

https://www.google.com/search?q=Karna+Fault

Arjuna in Comparision

Pariksit Maharaja compared that "My grandfather was just like an ordinary fish, and these soldiers, these commanders, (were) just like timingila." Timingila, there is a fish—we get information from Vedic literature—very big fish. They swallow up the whales. Timi. Timi means whale fish. And timingila means... Just like small fish are swallowed up like this. So just imagine how big such fish is. So these commanders, Karna, Dronacarya, and Bhisma, were compared with the timingila. And Arjuna although very powerful, he was compared with timi. So Pariksit Maharaja admitted "That it was not possible for my grandfather to win over the battle before these big, big commanders. It is only by the grace of Krishna he was saved." So the conclusion is if Krishna saves, nobody can kill; and if Krishna wants to kill, nobody can save. Bhagavad-gita 1.2-3
http://folknet.in/SS2008/html/images/Srila%20Prabhupada/SP%20vani/Lectures/BG%201.02.pdf