agent who is free from attachment, non-egoistic, endowed with firmness and enthusiasm, and
unaffected by success or failure, is called sattvika (pure).
Passionate, desiring to obtain the reward of actions, greedy, cruel, impure, moved by joy and sorrow, such an agent is said to be rajasa (passionate).
Unsteady, vulgar, unbending, cheating, malicious, lazy, desponding and procrastinating - such an agent is called tamasa.
If the light within (knowledge) that illumines our life and the actions that proceed in that light are sattvika or pure, obviously the agent will also be pure. But no. Krishna does not let us take anything for granted. In the bloodless, weaponless inner warfare, a moment's non-vigilance might undo a lifetime's hard work. The inner agent (the ignorance-born ego) cannot be destroyed because it is a shadow. It has to be discovered.
In reality, the ego (the agent) is not a devil, but God asleep. The veil of ignorance or deep sleep has to be removed. This is achieved by sattva (the quality, "va," of reality, "sat"). The agent with the veil on is the little self or ego; the agent minus the veil is the self identical with the supreme self whose thought is spread out as the universe and whose will maintains the cosmic play. Sun shines, earth revolves - but ignorance calls it the passage of time! There is a constant change of atoms in this universe; the ego superimposes on this an endless series of concepts - birth, death, success, failure, pain, pleasure, heat, cold, etc.
Thus deluded, the ego lives a completely isolated and self-centered life (tamasa). By evolution and effort it graduates to the passionate life (rajasa). Then, through deliberate avoidance of the nature of the above two, and by the conscious cultivation of the sattvika attitude, the ego becomes non-ego, joyously surrendering to the divine, participating in God's will and enjoying the bliss that he is.
Web Editor's Notes