Below is the summary of the third and fourth sections of the Yoga Sutra, which completes it.
Vibhuti Pada: This section covers the remaining three limbs of Ashtanga which are Dharana (concentration), Dhyana (meditation), and Samadhi (Connecting with the Divine). The term Vibhuti has multiple meanings and the most common one is Sacred Ashes. However, the one that best suits this section of Yoga Sutra would be after burning the body in holy fire of Yoga; our body turns into sacred ashes. Another interesting thing to note is, in the entire section of Vibhuti Pada the word ‘Vibhuti’ has not been used even once.
Vibhuti Pada has fifty five Sutras in it that contains detailed explanation on reaching the Samadhi stage, by learning to concentrate on the breathing system (Dharana) and by meditating (Dhyana) on the divine. It also states that to successfully achieve this one needs to purify the heart and clear the mind.
Kaivalya Pada: The last word used in Vibhuti Pada is Kaivalyam which means detachment from the material world. With thirty four Sutras under this section which guides the reader step by step, about what comes after Samadhi.
Reaching to this stage, the individual gains an amazing feeling of being one with the universe. There are no sorrows or happiness there is only peace and contentment for the one who has successfully attained Kaivalyam. This should not deter us from living our lives, normally. A person continues to do all their material duties however without keeping any high expectations or with the greed for anything.