PYS I.2 yogaś citta-vritti-nirodhah
When you stop identifying with your thoughts, fluctuations of mind, then there is Yoga, identity with Self, which is samadhi, happiness, bliss and ecstasy.
Yoga is the state of samadhi, the state of bliss, the state of enlightenment. Citta vritti is mindstuff or fluctuations of the mind. It is the endless chattering of the mind. Nirodhah means to stop. In this yoga sutra, it is said that enlightenment happens when the chattering of the mind stops.
The mind does that constantly-- the endless chitchat, on and on and on. What am I going to do after class? It's so hot here. What time is it going to be over? I wonder if anyone texted me. When's the next holiday break? Some citta vrittis are stubborn recurring themes that take over our vision of reality: I am not good enough, strong enough, thin enough, smart enough, pretty enough, popular enough, smart enough, rich enough, so on and so forth. The danger in these citta vrittis is that we may sometimes mistake them for our reality. We may get so absorbed in them that we start to believe these citta vrittis as our truth. And to overcompensate, we let the ego take over. And then we think that in order to be good enough, we must do this and that, become this and that, and when these things don't happen, we feel that life has no meaning, because our sense of self was hinging on the chattering of the mind-- an illusion-- in the first place. So we'll turn it backwards. To find the meaning of life, we want to cut through the unnecessary things, cut through our ego tendencies, cut through our citta vrittis, and realize and accept that the only meaning in life is to live. It's not to be perfect, it's not to be someone we are not, it's not to chase what is outside of us. It is simply to live.
Citta vrittis are constantly there, haunting us and taunting us. The practices of yoga allow us to create space between the witness consciousness and the thoughts. As a sakshi observing the mind and its citta vrittis, we then start to have an experience of the self not as the thoughts but as separate from the thoughts. We are not our citta vrittis. We are not our mind. We are not our body. We are the consciousness that drives this body and mind. In those brief moments that the fluctuations of the mind stop and we find that inner stillness, the present moment becomes so vibrant it needs no external influences for it to be meaningful. It just is. Life just is.