Chapter-1, Sutra 4

Patanjali Yogasutra Verse 1.4 

वृत्तिसारूप्यमितरत्र

At other times, the seer identifies with the fluctuations of the mind.

This Sutra explains the condition of the ordinary human being, who is not established in the True Nature of the Self, but is constantly influenced by the changing states of the mind. The mind is composed of various thoughts, feelings, memories, desires, and impressions, which are called vṛttis. These vṛttis are constantly arising and subsiding in the mind, creating a stream of consciousness that is often turbulent and restless.

The seer (soul), or the Pure Consciousness, is the witness of the mind and its vṛttis, but not affected by them. However, due to ignorance and attachment, the seer forgets its own nature and identifies with the vṛttis, as if they were its own. This identification leads to the loss of discrimination and the bondage to the cycle of birth and death. The seer becomes entangled in the joys and sorrows, the likes and dislikes, and the virtues and vices of the mind.

The purpose of Yoga is to break this identification and to restore the seer to its original state of freedom and Bliss. By practicing the various aspects of yoga, such as ethical conduct, self-discipline, physical postures, breath control, sensory withdrawal, concentration, meditation, and absorption, the seer gradually detaches itself from the vṛttis and becomes aware of its own nature, which is beyond all modifications and limitations. This is the state of Self-Realization or Enlightenment, the Ultimate Goal of yoga.

There are many verses from other Vedic texts that convey a similar message as the Patanjali Yogasutra Verse 1.4. 

- From the Bhagavad Gita (Chapter 6, Verse 25):

शनैः शनैरुपरमेद् बुद्ध्या धृतिगृहीतया|

आत्मसंस्थं मनः कृत्वा न किञ्चिदपि चिन्तयेत् ||

Gradually, with the intellect firmly established in patience, making the mind abide in the Self, one should not think of anything else.

This verse describes the process of meditation, which is the means to attain the state of Self-Realization. It advises the seeker to withdraw the mind from the external objects and focus it on the Self, which is the source of all peace and happiness. It also cautions the seeker to be patient and persistent in the practice, and not to be distracted by any other thoughts or desires.