Kaivalya Pada is the fourth and final part of Patanjali’s Yoga Sutra. Kaivalya also means eternal emancipation. The yogi, who reaches the sublime state of yoga, begins to experience supra-normal powers. 

Patanjali says these could also be a trick to prevent the yogi from attaining the true aim of yoga, which is Kaivalya (isolation) a state of exalted intelligence*. 

For the attainment of such a state, he should spurn the distraction of these extraordinary powers and also discern and subdue the aham (the feeling of ‘I’) caused by them. He should always keep his consciousness pure and serene.

* Sri Aurobindo calls this ‘Supramental state’

Patanjali advises that after reaching the state of enlightenment, the yogi should live to serve humanity with his supreme wisdom. 

Once the soul is liberated from the oppression of the body and mind, the lures of power, pride or success do not affect him. This is the state of Kaivalya which grants the yogi absolute freedom.