YS III - 50, 51

Yoga Sutra III- 50 -SATTVA PURUSANYATAKHYATIMATRASYA SARVA BHAVADHISTHATRTVAM SARVAJNATRTVAM CA - By recognition of the distinction between sattva (the pure reflective nature) and the Self, supremacy over all states and forms of existence [omnipotence] is gained as is omnisicience.

Yoga Sutra III - 51 - TAD VAIRAGYAD API DOSA BIJA KSAYE KAIVALYASM - By non-attachment even to that [all these siddhis], the seed of bondage is destroyed and thus follows Kaivalya (Independence).

Swami Satchidananda translated sutra 50 without commentary. In regard to sutra 51 he states "This means that all these siddhis are beautiful, but they will bind us, because siddhis are the outcome of the mind. The mind wants something. It wants to achieve this or that. What for? To be proud of itself. It develops ego. It makes your "I" and "mine" bigger. Selfish desires are still there. If you are after siddhis like astral traveling, clairvoyance and clairaudience, I ask you why. You may say, 'Oh, I thought I could help people.' I say that is just an excuse. You want to show you can do something. You want to be proud of it."

Swami Satchidananda then asks are siddhis bad, and if so why do they exist. He answers that the siddhis are beautiful and good when they come to you. When we run after them then it is bad. "That's all the difference. Let the siddhis come and beg,..." We are also told that the siddhis are "God's powers, by-products of the search for Him. Let them come after you."

Finally he tells us "Patanjali clearly explains these things, because as a scientist he has to place the facts before his students. But is is not that he is encouraging you to acquire siddhis. That is the beauty of Patanjali. He is not hiding anything." The possibilities are given to us, but don't run after them as we can get hurt.

For the above sutras there is only a commentary on Yoga Sutra III- 51 from "How to Know God - The Yoga Aphorisms of Patanjali" translated and commented on by Swami Prabhavananda and Christopher Isherwood:

We are told "The 'seed of evil' is ignorance." It is because of this ignorance that we forget the we are the "Atman" and creates a separate ego-personality. "Of all powers, the psychic powers are, from the standpoint of the ego, the most desirable;". "The yogi who has held even these powers within his grasp and nevertheless renounced them, has rejected the ultimate temptation of the ego. Hence he is free from bondage."