Sutra 1.2Yoga happens when there is stilling (in the sense of continual and vigilant watchfulness) of the movement of thought – without which there is no movement.

Sutra 1.3. Then the Seer abides in Itself, resting in its own True Nature, which is called Self-realization.

Sutra 1.4. At other times, when one is not in Self-realization, the Seer appears to take on the form of the modifications of the mind field, taking on the identity of those thought patterns.

Sutra 1.12. These thought patterns are mastered regulated, coordinated, controlled, stilled, quieted) through practice and non-attachment.

Sutra 1.14. This practice becomes well-grounded when continued with reverent devotion and without interruption over a long period of time.

Sutra 1.41. When the modifications of mind have become weakened, the mind becomes like a transparent crystal, and thus can easily take on the qualities of whatever object observed, whether that object be the observer, the means of observing, or an object observed, in a process of engrossment called samapatti.