Then, when the past and present mental content are identical, the transformation of one-pointedness arises.

Śānta is what has passed, what is quieted. Udita is what has arisen, what is present. Tulya is equal, identical. Pratyaya is mental content.

This is the third parināma, the most subtle. The cognition of the past moment and that of the present moment are exactly the same.

Normally, each moment brings a different thought. Here, moment after moment, the mind remains on the same object without variation.

It is the deepening of ekāgratā. Not only is there one object, but the perception of that object is identical from one instant to the next.

Commentators compare it to a thread of oil flowing without ripples. The continuity is perfect.

This parināma is the foundation of deep samādhi. When the mind can sustain this identity moment to moment, it is ready for higher knowledge.