Niyamas: (Personal Disciplines): The niyamas are the second constituents of Ashtanga Yoga. How we interact with ourselves, own physical appearance, actions, words and thoughts. The niyamas are about self-regulation—helping us maintain a positive environment in which to grow. Their practice harnesses the energy generated from the cultivation of the earlier yamas.

According to the Bhagavad Gita lists 11 constituents. But Patanjali names only five:
* Shoucha - Purity
* Santosh - Contentment
* Tapa - Endurance
* Swadhyaya- Self study
* Eshwar Pranidhan- Dedication

Shoucha (Purity):
This means the purity. Like ahimsa, this purity is also physical, oral and mental. Physical purity is again divided into two parts, outer and inner. Yoga has considered all types of purity and given directions as to how to achieve it. However, Patanjal Yoga does not give detailed description of this. But it is stated in detail in Hatha yoga.

While considering outer purity, Hatha yoga describes many processes right from brushing the teeth. The specific powder (churna) that should be used for cleaning the teeth is also mentioned under Shuddhikriya in Hatha yoga.
There are six types of shuddhikriyas for the internal purity. Dhouti, Basti, Neti, Tratak, Nouli and Kapalbhati. Just the statement that internal purity has been considered in the minutest detail by yoga is enough.

For oral purity, yoga has given the message that one should not talk too much. Unnecessary use of the tongue is to be avoided and following the yama should purify the tongue. Yoga has accepted the inseparable relation of the body and the mind. Hence, each and every yogic process affects the body as well as the mind. Also, for purifying the mind, there is a process known as Trataka. We will consider it in detail afterwards.

The following aphorism states the result of the shoucha:
After purity is achieved by this process, sadhaka loses the feeling of the importance of the body and does not wish to interact with the other bodies.
When the sadhaka starts purifying the body, he feels that the body is full of impurities and he feels disgusted about it. When such feelings arise, he tries to avoid even the touch of the other and engages himself in his own mental bliss.
Patanjali has stated in another aphorism that:
the purification process, satvashuddhi, mental happiness, calm mind, victory over the organs, and the plan to view the self (atma) are achieved............................................................................................................TOP

Santosh (Contentment):
Contentment is also an important virtue. When we observe the never-ending efforts of all creatures in their day-to-day lives, and think of the purpose behind it, we realise that all these efforts are to gain mental contentment and peace. We try to derive the contentment from outside matters. However, none is aware of the fact that the contentment does not depend upon these outside matters. It is a state of mind. It is not a reaction of the mind on any incident. Hence, it can be controlled irrespective of the incidents. Yoga with the use of this word intends the hidden meaning that one should learn to be happy in what one gets. This attitude will reduce pain and suffering in life. However, there should be mental preparation for this. When this tendency to feel contented is adopted by the mind, the perpetual happiness is not far behind. In fact the root of happiness lies in this tendency of the mind. And the root cause of suffering is in Trishna.

This trishna has been defined in one Sanskrit shloka as under:
Asha nam manushyanamkachitdashwaryashrunkhala |
Yaya baddha pradhavanti muktastishathatipanguvat ||

Hope is such a chain that when tied with it, the creature starts running and when released from it, the creature stands peacefully.

Running behind the hope will lead to only pain and suffering.

Patanjali has given the following aphorism while describing the results of the contentment:
One who constantly learns to be contented, all his thirst gets weakened and the satva is heightened. He gets the maximum happiness and feels that pleasures from heavens or even the place of the God Indra is also nothing as compared to his own bliss.........................................................................................................TOP

Tapa (Endurance):
Tapa means to bear some trouble with a good intention. Even if there is some physical or mental trouble, one should not discontinue his actions, but should continue them. This is known as Tapa. While studying Yoga or practising some yogic process, there may be some physical trouble. One should bear it happily and should pursue his studies. This is tapa.

The seventeenth chapter of Bhagwad Gita has described Tapa. There are three types of tapa: Satwik, Rajas and Tamas. Tapa done with faith and without hoping for the fruits is Satwik. That which is done for the expectation of status, felicitation etc is known as rajas tapa. And tapa arising out of folly, with some trouble to the body and with the intention of creating trouble for the others is tamas tapa. Patanjali has stated the results of the tapa in the following aphorism:

Ashuddhi is adharma. It is a tamas guna. It is impurity, which veils the siddhis such as Anima. The daily practice and study of tapa , after its completion, removes all such impurities. When ashuddhi or impurities are removed, then siddhis such as Anima, Mahima, Lachima etc are obtained...............................................TOP

Swadhyaya (Self Study):
Ishwar gita while describing swadhyaya has stated that japa is swadhyaya. It includes both shrawan and manan (listening and contemplation). Japa is of two types, oral and mental. Again oral japa is of two types, audible - with loud chanting which can be heard by the others and inaudible - whispers which cannot be heard by others. Mental japa is also of two types - without dhyana and with dhyana. In all these japas, japa without dhyana is considered as the best.

In daily life of commoners, swadhyaya can be said to mean revision of what is taught.
The results of swadhyaya are as under:
While doing japa of a particular mantra, when an anushtan is completed, the goddess for whom the japa is made becomes pleased with the sadhaka and appears before him. (Known as darshan)

Ishwar pranidhan (Worship with complete faith):
It means while believing in the existence of God and having faith in his greatness, completely devoting oneself to Him without any expectations in return. There is some divine strength at the root of this universe, which is beyond our imagination. To identify the divine strength and to surrender one completely to it is ishwarpranidhan.
There are nine types of devotions for God:
Shrawanam Kirtanam Vishnoh smaranat padsevanam |
Archanam Vandanam dasyam sakhyam atmanivedanam ||

At times, even after our persistent efforts, we are unable to succeed. At such a time, if we have compassion of the God, the problem gets solved.
With Ishwarpranidhan, the siddhi of samadhi can be obtained.

There are five niyam in Patanjal Yoga. However, Hathapradeepika states ten niyam.
Tapahsantosh aastikyaam danamishwar poojanam |
Siddhantavakyashravanam hrimatich japo hutam ||
Niyama dash samprokta yogashastra vishardai || H P

The ten Niyama are Tapa, Santosh, Aastikya, Dan, Ishwarpujan, Siddhanta- Vakya shravan, Lajja, Mati, Japa and Hom. We have considered Tapa, Santosh, Ishwarpujan and Japa. We will consider the remaining six.

Apart from these five constituents another six constituents are described in Bhagabata Gita.
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