Some Main Hindu Themes found in the Bhagavad Gita

1) dharma: caste duty
2) immortality (of atman)
3) reincarnation or rebirth
4) the embodied/body distinction
5) karma: action
6) bondage to karma
7) karma yoga: disciplined action
8) acting for the fruits of action
9) acting for the sake of the action
10) indifference to opposites
11) maya: jungle of delusion
12) desire
13) possessed of the Self (atman)
14) peace, tranquility
15) the "I-maker"
16) self interest or egoism
17) nirvana: blowing out
18) brahman
19) spiritual/material world
20) moksha: release or liberation (from the material world)