These three [Dhāraṇā, Dhyāna, Samādhi] are internal, compared to the preceding [five].

Patañjali distinguishes these three limbs (Dhāraṇā, Dhyāna, Samādhi) as more internal, more subtle, than the first five limbs of Aṣṭāṅga-yoga (Yama, Niyama, Āsana, Prāṇāyāma, Pratyāhāra). This is because these three use the more internal, deeper mind, compared to the other five, which use external faculties such as the body, senses and breath. Compared to the first five, these three are achievements, rather than practices.

Its appropriate application is in stages.

In this Sūtra, Patañjali presents the remarkable concept of Viniyoga. The object of enquiry must be chosen with due appreciation of our potential. When one is at a beginner’s level, advanced practices are not suitable, and when one is at an advanced level, lower levels are worthless. Our predispositions, latent impressions, habits, personality and other factors must all be taken into consideration. This is where again the appropriate guidance of a teacher is invaluable.

From its mastery, dawns the light of supreme knowledge.

Saṁyama on a chosen object leads to a comprehensive knowledge of all its aspects. More interestingly, it will reveal one’s own true nature. For example, take the case of someone who is a lifelong photographer. She may have mastery over her field and can take brilliant photographs very easily. However, it is the quality of the photographs and the themes she chooses which reveal her true nature, which shines through her work.

The three unified together in one [object, or direction is called] Saṁyama.

The meditative process of Dhāraṇā, Dhyāna and Samādhi can be used over time with different objects of focus. Saṁyama is a technical term referring to Dhāraṇā, Dhyāna and Samādhi, sustained with the same object of focus, for a long time.

[When, in] that [meditation], only the object of focus shines radiantly and [the meditator is as if] devoid of Its own nature, this is spiritual absorption.

Samādhi is a state of complete spiritual absorption and is an extension of Dhyāna. The meditator is so involved in the object of focus, that nothing except its awareness exists.

Once the direction is fixed and sustained, a link develops between the mind and the chosen object of focus.

Meditation is the continuation of awareness therein.

Steadiness is confinement of the mind to one [chosen] place [or in a chosen direction].

The object of focus is chosen carefully by the individual who has a settled mind. The chosen object may be material or conceptual, tangible or intangible, gross or subtle.

From this comes supreme mastery of the senses.

The senses not only begin to cooperate with the mind, they become very sharp and are able to grasp very subtle objects as well. This is why Yogin-s have such refined levels of perception.

Being disconnected from their own [usual external] objects, following the inward movement of the mind as if it were their own, is restraint of the senses.

Normally, when the senses are active, they turn outwards, pursuing objects outside us. However, as Vedavyäsa says in his commentary when the Yogin is directing the mind to a chosen focus, the senses withdraw and follow this inner movement of the mind, just as bees follow their Queen.

And the mind becomes fit for steadiness.

Only a still mind can be fit for Dhāraṇā, which is the first step toward meditation. Patañjali offers many kinds of meditation practice in the third chapter. As each commences with Dhāraṇā, Prāṇāyāma is an obvious pre-requisite for all meditative practices.

Then, the veil [covering] the [inner] light is removed.

The veil that covers the inner light is blown away by Prāṇāyāma, just as clouds covering the sun are blown away by the wind. Then the mind, cleansed of its toxins, reflects the light shining within our heart.

The fourth [state of Prāṇāyāma] transcends the domain of the external and the internal.

The first three levels of Prāṇāyāma relate to the control of exhalation, inhalation and suspension of breath. However, here the fourth level is described, where the Yogin is in a state of Yoga, and no longer needs to regulate the breath.

[In Prāṇāyāma, when] the exhalation, inhalation and suspension of breath are regulated with regard to place, duration and number [of repetitions], [the breath becomes] long and smooth.

In this Sūtra, Patañjali lays out the framework for practicing Prāṇāyāma. The three components of breath are exhalation, inhalation and suspension. They must be regulated in place, duration and number of repetitions.

Through Āsana practice, we slowly understand how the breath behaves. Breathing patterns vary as a result of our state of mind or bodily changes, which can be caused by both internal and external forces. This knowledge of the breath, gained through Āsana practice, becomes the foundation for Prāṇāyāma.

On its achievement, Prāṇāyāma, conscious and deliberate regulation of the breath, is the cessation of disturbed and unconscious inhalation and exhalation.

Consequently, the suspension of disturbance from the polarities.

Our life is dominated by polarities. Pain and pleasure influence us very easily. So do loss and gain, failure and success, heat and cold, dynamic and static, masculine and feminine etc. Vedic philosophy teaches that we are influenced by at least ten pairs of opposites.

How can we achieve these qualities of Āsana?

[These dual qualities arise through] appropriate effort without tension, and meditation on the infinite.

Patañjali reminds us that while practising Āsana, it is important that the effort is both appropriate and without tension. The body must not be pushed merely to achieve a form. Appropriateness also takes into consideration the constitution of the practitioner, age, capacity, season and other pertinent factors.

Patañjali now presents Āsana and Prāṇāyāma, the next two limbs of Yoga, and how to practice them appropriately. It is easier to begin with them, but the other limbs must not be forgotten, especially the first two. The instructions that follow are brief because these practices must be learnt directly from a competent teacher.

Posture [must] have [the dual qualities of] steadiness and comfort.

Accomplishment in spiritual absorption comes through surrendering to the Divine.

Actions done in the spirit of service promote the ability to remain steady and focused, thus leading to Samādhi. Patañjali makes it clear through this Sūtra that success in Samādhi is possible only through Īśvara-praṇidhāna. It must be remembered that Īśvara-praṇidhāna for atheists or non-believers could be a surrender to Universal Consciousness, or whatever seems appropriate, providing that it is something beyond the small idea of the Self.

Through [mastery of] self-enquiry comes communion with the desired deity.

Self-enquiry (Svādhyāya) involves the study of sacred texts that belong to our tradition and is usually reinforced through the recitation of Mantra-s. These will bring us closer to the deity of our choice, giving us light, strength and guidance on our spiritual journey.

Perfection of the body and senses arises through self-discipline that removes the toxins.

Through appropriate practices of self-discipline, the body and mind are rid of impurities and hence begin to function more efficiently.