Chapter-3, Sutra 18

Patanjali Yogasutra 3.18

 संस्कारसाक्षात्करणात्पूर्वजातिज्ञानम्।

"By the direct perception of one's past mental impressions (samskaras), knowledge of previous births is attained."

In this Sutra, Patanjali speaks about the extraordinary capability of discerning one’s past lives by observing and understanding the deep-seated impressions (samskaras) that reside within the mind. 

Samskaras are mental imprints formed from past experiences and actions, stored in the subconscious. Through dedicated practice of meditation and Self-Realization, the practitioner can gain access to these impressions and thus retrieve information about previous incarnations.

This knowledge is not mere recollection of external events, but an awareness of the continuity of the soul’s journey through time. In this state of Higher Consciousness, the yogi transcends the limitations of present life and taps into the deeper layers of existence, where the 

samskaras of countless past lives are recorded. Understanding these 

samskaras allows the yogi to comprehend patterns of behavior, tendencies, and the causes of one’s current existential situation.

In the broader context of yoga, this Sutra signifies that a true yogi, with purified Consciousness, gains insight into the nature of their soul’s journey. 

The knowledge of past lives not only helps in the spiritual evolution of the practitioner but also provides clarity about the karmic consequences of actions taken in prior births, leading to a more profound understanding of the cycle of birth, death, and rebirth.

Swami Vivekanand said:

"Each experience that we have comes in the form of a wave in the Chitta, and this subsides and becomes finer and finer, but is never lost. It remains there in minute form, and if we can bring this wave up again, it becomes memory. So, if the Yogi can make a Samyama on these past impressions in the mind, he will begin to remember all his past lives."

Comparative Verses from Other Vedic Texts:

Brihadaranyaka Upanishad 4.4.5 

स यथाकामो भवति तत्क्रतुर भवति । यत्क्रतुर भवति तत्कर्म कुरुते । यत्कर्म कुरुते तदभिसंपद्यते ॥

"As a person desires, so is their will; as their will, so is their deed; and as they do, so they become."

This verse from the Brihadaranyaka Upanishad speaks of how a person's desires and actions (karma) shape their future, which parallels the idea of samskaras shaping future births in the Yogasutra. Both texts emphasize that mental impressions and actions from previous lives influence current and future existence. The Upanishad underscores the notion that one's inner world directly impacts one's reality, much like the Yogasutra emphasizes 

samskaras shaping rebirths.

Bhagavad Gita 8.6 

यं यं वापि स्मरन्भावं त्यजत्यन्ते कलेवरम्। तं तमेवैति कौन्तेय सदा तद्भावभावितः॥

"Whatever State of Being one remembers at the time of death, that State they will attain, O Arjuna, because of their Constant Remembrance on it."

This verse from the Bhagavad Gita complements Patanjali's Sutra by illustrating how thoughts and impressions at the time of death shape the future existence. While Patanjali's Sutra focuses on the ability to recall past lives through samskaras, the Bhagavad Gita points to the fact that one's final thoughts at death—strongly influenced by past samskaras -determine the nature of the next birth.

Yoga Vashishta 6.1.12 

वासनातन्मयं विश्वं वासनासु विवर्तते। वासनानां क्षये नष्टं बन्धमोक्षौ ततो भवेत्॥

"The world is a projection of one’s mental impressions (vasanas). As these impressions transform, so does the world. When these vasanas are exhausted, liberation (moksha) is attained, and both bondage and freedom vanish."

This verse from the Yoga Vashishta aligns with Patanjali’s teaching on samskaras, emphasizing that the entire universe is experienced through the lens of mental impressions. Both texts highlight that it is through understanding and dissolving these impressions that one can achieve liberation. The Yoga Vashishta also stresses the cessation of vasanas 

(impressions) as the Ultimate Goal for Realization, which echoes Patanjali’s broader goals of freeing oneself from the cycle of rebirth through understanding samskaras.