The whole of prakriti or nature is constituted of the three gunas, satva, rajas and tamas, and the Lord is the creator and controller of these. But He is not under their sway. Among them, Satva is superior to rajas and rajas better than tamas. People, the wealthy, the strong, the intelligent, are all bound by the gunas that are nothing but mental states, temperaments or thoughts. So, everyone is a necessary combination of the three gunas.
But human beings are blessed having been given a choice to improve and try to convert from tamas to rajas and then to satva, pointed out Srimati Sunanda in a discourse. The nature of satva is shown to be expressed as calmness, purity, tranquillity, harmony and a sense of equilibrium. When satva prevails, one is calm and serene and has noble thoughts. Rajas is seen as activity in desire, power and energy and so when rajas is dominant, one is hopeful, ambitious and so on. Tamas is seen as inertia and is expressed as dullness, laziness, weakness, etc. When under tamas, one tends to lack incentive. Moreover, the three gunas and their manifestations in the universe keep the people engrossed in the world to such an extent that they do not recognise the Paramatma, who is their cause, even as the sun is not perceived by people when it is hidden behind the clouds.
One should train oneself to identify the inherent predominant tendency in oneself that governs the nature of one’s thoughts. By practice of bhakti, vairagya, nishkama karma and so on, it is possible to shed the effects of tamas and rajas and maintain satva. But one has to learn to rise above satva too, says Krishna. Only then is he a Gunatita and is eligible to be established in atma jnana. As long as one is ruled by the gunas, one cannot hope for salvation.