Jñānaṁ bandhaḥ ज्ञानं बन्धः॥ (sūtra III.2)
Jñānaṁ - knowledge; bandhaḥ - bondage.
(The second sūtra of the first section also says, Jñānaṁ bandhaḥ and its brief interpretation provided therein is as follows: Supreme knowledge is the experience of the mind and not derived through sensory experience. Knowledge conceived, nurtured and manifested by the mind remains uncontaminated with temporal matters such as bondage.)
The previous sūtra (III.1) said that a normal mind works on three constituents - mind, intellect and ego. In the present section, knowledge means the knowledge arising out of the mind influenced by the said three constituents. Knowledge acquired through sensory perceptions are said to be limited because of the influence of māya or illusion. Illusionary influence on the mind binds an individual becomes the cause to get involved in actions without surrendering the effects of such actions to God. Unless one makes considerable spiritual progression by getting rid of ego, the concept surrender does not imbibe. Ultimately, it is only the afflicted mind that is responsible for transmigration of soul. It is unable to differentiate between what is real and unreal and gets addicted to pleasures of life. On the contrary, a purified mind is the one where the sensory influence is at the minimal level. A purified mind is tamed in such a way that it is able to differentiate between what is permanent and what is impermanent.
This sūtra says that it is only the knowledge that differentiates between permanency (God) and impermanency (material objects) causes bondage. This differentiation is caused by māya or illusion. The Reality is that the Lord alone is permanent and everything else is impermanent. If this fact is understood, the mind gets released from the clutches of bondage.
Kṛṣṇa says in Bhagavad Gīta (V.21 and 22), “He whose mind remains unattached to sense objects, derives through mediation the joy that dwells in the mind; then that yogi, having completely identified himself though mediation with Brahman, enjoys eternal bliss. The pleasures which are born of sense-contact are verily a source of suffering only. They have a beginning and an end. It is for this reason a wise man does not indulge in them.”