Srimad Bhagavad-Gita :
Chapter-2. ( Samkya-yogam )
Slokam-33. ( Lord Krishna responds to the distress of Arjuna to face his teacher and Pithamaha in the battle, This slokam illustrates the disadvantage of Arjuna acting contrary to his duty as a kshatriya. )
Atha cet-tvam-imam dharmyam samgraamam na karishyasi,
Tatah sva-dharmam keertim ca hitva papam-avapsyasi.
atha dharmyam imam samgraamam = hereafter, this dharmic ( based on dharmam ) war;
tvam na karishyasi cet = if you ( Arjuna ) do not perform ( fight );
tatah sva-dharmam = thereafter your own duty ( svs-dharmam of kshatriyan );
keertim ca hitva = loose ( your ) reputation/fame also;
papam-avapsyasi = you will earn ( gain ) sinful reaction.
If, however, you do not fight this (svadharmam) war, then you will certainly incur sins for neglecting your duties and thus lose your reputation as a fighter.
If through injudicious sentiment or bewildered ignorance Arjuna should fail to perform his prescribed duty as a ksatriya by fighting for the sake of righteousness; he would lose a most excellent opportunity of attaining the heavenly spheres, he would lose his reputation as a hero and he would have to accept great sinful reaction.
Now Lord Krishna responds to Arjuna's previous distress of not wanting to slay his enemies such as Bhishma and Drona but instead to allow his enemies to slay him. The use of the word atha is to emphasise another point of view that if Arjuna declines to fight this righteous war and chooses to disregard the acquisition of happiness in either this world or the heavenly worlds as enjoined in the Vedic scriptures which state that the royal orders should conquer over his enemies and rule over the earth. Then by refusing to accept his responsibility and avoiding the battle Arjuna would be abandoning his duty which brings rewards and boundless glory and thus losing his reputation both worldly and divine which results from the victory of a great warrior Arjuna would in fact incur great sin.
Arjuna was a famous fighter, and he attained fame by fighting many great demigods ( devas of devalokam ), including even Lord Siva. After fighting and defeating Lord Siva in the dress of a hunter( in disguise to test Arjuna ), Arjuna pleased the Lord and received as a reward a weapon called pasupata-astra. Everyone knew that he was a great warrior. Even Dronacarya gave him benediction and awarded him the special weapon by which he could kill even his teacher. So he was credited with so many military certificates from many authorities, including his adopted father Indra, the heavenly king. But if he abandoned the battle, he would not only neglect his specific duty as a kṣatriya, but he would lose all his fame and good name and thus prepare his royal road to hell. In other words, he would go to hell, not by fighting, but by withdrawing from battle.
To be continued ...
Swami Sri Chinmayananda with Sri Sathya Sai Baba