|Chapter 2: Contents of the Gita Summarized|
sva-dharmam api cavekshya
na vikampitum arhasi
dharmyad dhi yuddhac chreyo 'nyat
kshatriyasya na vidyate
Considering your specific duty as a kshatriya, you should know that there is no better engagement for you than fighting on religious principles; and so there is no need for hesitation.
The main theme in the next set of verses (2.31-2.38) is that material happiness comes from the execution of one's duties. Neglect of these duties brings material downfall. This section is an elaboration of the verse 2.2 where in Krishna first says to Arjuna that non-performance of his duties will lead to hellish planets (asvargayam) and infamy (akirti).
Krishna will now drop His argument to a materialistic level. Having successfully defeated Arjuna's argument of compassion based on sankhya or jnana (knowledge), He will now defeat Arjuna's arguments (in 1.32-35, 2.7-8) that by fighting he could not enjoy.
Many people get confused on reading this section of the Gita. Right after Krishna has given an exalted philosophical dissertation on the soul (2.11-30), He turns around and glorifies the maintenance of one's good name in the society and enjoyment of material comforts.
This is a constant recurrence in the Bhagavad-gita, where in Krishna seems to glorify contradictory approaches. This confusion is rectified when one sees the instructions in accordance with the context. The Gita is meant for all people at varying levels of advancement and realizations whether they are vikarmis (sinful), karmis (pious), jnanis (learned), yogis or bhaktas. Krishna gives specific instructions addressed at each of these levels and hence the apparent contradictions. Of course Krishna also resolves these contradictions by explaining and collating the context.
Srila Prabhupada explains that the "sva-dharma" or prescribed duty of a ksatriya is to fight on religious principles and in doing so they achieve elevation to the higher planetary systems.
Please read the Sanskrit Verse and the Prabhupada's Purport.